ABSTRACT
BACKGROUND: Artemether-lumefantrine (AL) is the first line anti-malarial drug for the treatment of uncomplicated malaria in Tanzania. The World Health Organization (WHO) recommends regular efficacy monitoring of anti-malarial drugs to inform case management policy decisions. This study assessed the safety and efficacy of AL for treating uncomplicated P. falciparum malaria in Tanzania in 2022. METHODS: Children 6 months to 10 years with uncomplicated P. falciparum malaria were recruited from four sentinel sites and treated with the standard 6 dose, 3-day regimen for AL. Clinical and parasitological responses were monitored for 28 days using the WHO standard protocol. Genotyping based on msp1, msp2 and glurp was used to distinguish recrudescence from reinfection. SANGER sequencing was used to detect K13 mutations. RESULTS: 352 participants, 88 per site, were enrolled. Four withdrew and 55 experienced parasite recurrence. The PCR corrected Kaplan-Meier efficacies were, 89.9% in Pwani, 95.0% in Kigoma, 94.4% in Tanga, and 98.9% in Morogoro. No K13 mutations were found. CONCLUSIONS: Artemether-lumefantrine remains highly efficacious in three regions of Tanzania but the PCR-corrected efficacy in Pwani fell below the WHO-defined 90% threshold at which policy change is recommended. Implementing strategies to diversify ACTs to ensure effective case management in Tanzania is critical.
ABSTRACT
BACKGROUND: Therapeutic efficacy studies (TESs) and detection of molecular markers of drug resistance are recommended by the World Health Organization (WHO) to monitor the efficacy of artemisinin-based combination therapy (ACT). This study assessed the trends of molecular markers of artemisinin resistance and/or reduced susceptibility to lumefantrine using samples collected in TES conducted in Mainland Tanzania from 2016 to 2021. METHODS: A total of 2,015 samples were collected during TES of artemether-lumefantrine at eight sentinel sites (in Kigoma, Mbeya, Morogoro, Mtwara, Mwanza, Pwani, Tabora, and Tanga regions) between 2016 and 2021. Photo-induced electron transfer polymerase chain reaction (PET-PCR) was used to confirm presence of malaria parasites before capillary sequencing, which targeted two genes: Plasmodium falciparum kelch 13 propeller domain (k13) and P. falciparum multidrug resistance 1 (pfmdr1). RESULTS: Sequencing success was ≥ 87.8%, and 1,724/1,769 (97.5%) k13 wild-type samples were detected. Thirty-seven (2.1%) samples had synonymous mutations and only eight (0.4%) had non-synonymous mutations in the k13 gene; seven of these were not validated by the WHO as molecular markers of resistance. One sample from Morogoro in 2020 had a k13 R622I mutation, which is a validated marker of artemisinin partial resistance. For pfmdr1, all except two samples carried N86 (wild-type), while mutations at Y184F increased from 33.9% in 2016 to about 60.5% in 2021, and only four samples (0.2%) had D1246Y mutations. pfmdr1 haplotypes were reported in 1,711 samples, with 985 (57.6%) NYD, 720 (42.1%) NFD, and six (0.4%) carrying minor haplotypes (three with NYY, 0.2%; YFD in two, 0.1%; and NFY in one sample, 0.1%). Between 2016 and 2021, NYD decreased from 66.1% to 45.2%, while NFD increased from 38.5% to 54.7%. CONCLUSION: This is the first report of the R622I (k13 validated mutation) in Tanzania. N86 and D1246 were nearly fixed, while increases in Y184F mutations and NFD haplotype were observed between 2016 and 2021. Despite the reports of artemisinin partial resistance in Rwanda and Uganda, this study did not report any other validated mutations in these study sites in Tanzania apart from R622I suggesting that intensified surveillance is urgently needed to monitor trends of drug resistance markers and their impact on the performance of ACT.
Subject(s)
Antimalarials , Artemisinins , Carubicin/analogs & derivatives , Malaria, Falciparum , Humans , Lumefantrine/pharmacology , Lumefantrine/therapeutic use , Plasmodium falciparum/genetics , Antimalarials/pharmacology , Antimalarials/therapeutic use , Tanzania , Artemisinins/pharmacology , Artemisinins/therapeutic use , Artemether/therapeutic use , Multidrug Resistance-Associated Proteins/genetics , Artemether, Lumefantrine Drug Combination/pharmacology , Artemether, Lumefantrine Drug Combination/therapeutic use , Malaria, Falciparum/epidemiology , Biomarkers , Drug Resistance/genetics , Protozoan Proteins/genetics , Protozoan Proteins/therapeutic useABSTRACT
Achieving malaria elimination requires considering both Plasmodium falciparum and non-P. falciparum infections. We determined prevalence and geographic distribution of 4 Plasmodium spp. by performing PCR on dried blood spots collected within 8 regions of Tanzania during 2017. Among 3,456 schoolchildren, 22% had P. falciparum, 24% had P. ovale spp., 4% had P. malariae, and 0.3% had P. vivax infections. Most (91%) schoolchildren with P. ovale infections had low parasite densities; 64% of P. ovale infections were single-species infections, and 35% of those were detected in low malaria endemic regions. P. malariae infections were predominantly (73%) co-infections with P. falciparum. P. vivax was detected mostly in northern and eastern regions. Co-infections with >1 non-P. falciparum species occurred in 43% of P. falciparum infections. A high prevalence of P. ovale infections exists among schoolchildren in Tanzania, underscoring the need for detection and treatment strategies that target non-P. falciparum species.
Subject(s)
Coinfection , Malaria, Falciparum , Malaria, Vivax , Malaria , Humans , Child , Plasmodium falciparum/genetics , Prevalence , Tanzania/epidemiology , Coinfection/epidemiology , Plasmodium malariae , Malaria/epidemiology , Malaria, Falciparum/epidemiology , Malaria, Falciparum/parasitology , Malaria, Vivax/parasitologyABSTRACT
BACKGROUND: Measurement of malaria prevalence is conventionally estimated through infrequent cross-sectional household surveys that do not provide continuous information regarding malaria parasitaemia. Recent studies have suggested that malaria parasitaemia prevalence among women attending antenatal care (ANC) correlates with prevalence among children under 5 years old and that pregnant women could be a sentinel population for tracking malaria prevalence. In mainland Tanzania, 97% of women are tested for malaria parasitaemia during first ANC visits. However, acceptability among pregnant women and healthcare providers of collecting malaria risk factor data during ANC visits is limited. METHODS: A tablet-based questionnaire including 15 questions on insecticide-treated net ownership and use and care-seeking for febrile children was introduced at 40 healthcare facilities in Geita Region, Tanzania. Facilities were randomly selected from among those with 15-120 first ANC visits per month. To assess perspectives regarding introduction of the questionnaire, 21 semi-structured interviews were held with providers and facility in-charges at 12 facilities. Thirty pregnant and recently delivered women participated in focus group discussions at seven facilities to assess the acceptability of spending additional time answering questions about malaria risk. RESULTS: All pregnant women reported that introduction of ANC surveillance and spending 10 more minutes with providers answering questions about their health would be neutral or beneficial. They perceived being asked about their health as standard of care. Providers and in-charges reported that introduction of ANC surveillance was within their scope of practice. Nine of 21 indicated it could potentially benefit women's health. Six providers expressed concern about staffing shortages and need for reimbursement for extra time and noted that data management occurs after hours. CONCLUSIONS: Pregnant women and providers generally perceived ANC surveillance for malaria as acceptable and positive. Pregnant and recently delivered women saw this as a reasonable and even helpful intervention. To be seen as a part of standard practice, efforts are needed to ensure providers perceive a benefit for ANC clients and that staffing concerns are addressed. In addition, staff should receive feedback related to data submissions regarding malaria prevalence and risk factors among women at their facility, with actions to take.
Subject(s)
Malaria , Prenatal Care , Child , Female , Humans , Pregnancy , Child, Preschool , Sentinel Surveillance , Tanzania/epidemiology , Cross-Sectional Studies , Feasibility Studies , Malaria/epidemiologyABSTRACT
BACKGROUND: Insecticide resistance is a serious threat to the continued effectiveness of insecticide-based malaria vector control measures, such as long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS). This paper describes trends and dynamics of insecticide resistance and its underlying mechanisms from annual resistance monitoring surveys on Anopheles gambiae sensu lato (s.l.) populations conducted across mainland Tanzania from 2004 to 2020. METHODS: The World Health Organization (WHO) standard protocols were used to assess susceptibility of the wild female An. gambiae s.l. mosquitoes to insecticides, with mosquitoes exposed to diagnostic concentrations of permethrin, deltamethrin, lambdacyhalothrin, bendiocarb, and pirimiphos-methyl. WHO test papers at 5× and 10× the diagnostic concentrations were used to assess the intensity of resistance to pyrethroids; synergist tests using piperonyl butoxide (PBO) were carried out in sites where mosquitoes were found to be resistant to pyrethroids. To estimate insecticide resistance trends from 2004 to 2020, percentage mortalities from each site and time point were aggregated and regression analysis of mortality versus the Julian dates of bioassays was performed. RESULTS: Percentage of sites with pyrethroid resistance increased from 0% in 2004 to more than 80% in the 2020, suggesting resistance has been spreading geographically. Results indicate a strong negative association (p = 0.0001) between pyrethroids susceptibility status and survey year. The regression model shows that by 2020 over 40% of An. gambiae mosquitoes survived exposure to pyrethroids at their respective diagnostic doses. A decreasing trend of An. gambiae susceptibility to bendiocarb was observed over time, but this was not statistically significant (p = 0.8413). Anopheles gambiae exhibited high level of susceptibility to the pirimiphos-methyl in sampled sites. CONCLUSIONS: Anopheles gambiae Tanzania's major malaria vector, is now resistant to pyrethroids across the country with resistance increasing in prevalence and intensity and has been spreading geographically. This calls for urgent action for efficient malaria vector control tools to sustain the gains obtained in malaria control. Strengthening insecticide resistance monitoring is important for its management through evidence generation for effective malaria vector control decision.
Subject(s)
Anopheles , Insecticides , Malaria , Pyrethrins , Animals , Female , Humans , Insecticide Resistance , Tanzania , Mosquito Vectors , Malaria/epidemiology , Malaria/prevention & control , Pyrethrins/pharmacology , Insecticides/pharmacology , Mosquito Control/methodsABSTRACT
BACKGROUND: Tanzania has made remarkable progress in reducing malaria burden and aims to transition from malaria control to sub-national elimination. In 2013, electronic weekly and monthly reporting platforms using the District Health Information System 2 (DHIS2) were introduced. Weekly reporting was implemented through the mobile phone-based Integrated Disease Surveillance and Response (eIDSR) platform and progressively scaled-up from 67 to 7471 (100%) public and private health facilities between 2013 and 2020. This study describes the roll-out and large-scale implementation of eIDSR and compares the consistency between weekly eIDSR and monthly DHIS2 malaria indicator data reporting, including an assessment of its usefulness for malaria outbreak detection and case-based surveillance (CBS) in low transmission areas. METHODS: The indicators included in the analysis were number of patients tested for malaria, number of confirmed malaria cases, and clinical cases (treated presumptively for malaria). The analysis described the time trends of reporting, testing, test positivity, and malaria cases between 2013 and 2021. For both weekly eIDSR and monthly DHIS2 data, comparisons of annual reporting completeness, malaria cases and annualized incidence were performed for 2020 and 2021; additionally, comparisons were stratified by malaria epidemiological strata (parasite prevalence: very low < 1%, low 1 ≤ 5%, moderate 5 ≤ 30%, and high > 30%). RESULTS: Weekly eIDSR reporting completeness steadily improved over time, with completeness being 90.2% in 2020 and 93.9% in 2021; conversely, monthly DHIS2 reporting completeness was 98.9% and 98.7% in 2020 and 2021, respectively. Weekly eIDSR reporting completeness and timeliness were highest in the very low epidemiological stratum. Annualized malaria incidence as reported by weekly eIDSR was 17.5% and 12.4% lower than reported by monthly DHIS2 in 2020 and 2021; for both 2020 and 2021, annualized incidence was similar across weekly and monthly data in the very low stratum. CONCLUSION: The concurrence of annualized weekly eIDSR and monthly DHIS2 reporting completeness, malaria cases and incidence in very low strata suggests that eIDSR could be useful tool for early outbreak detection, and the eIDSR platform could reliably be expanded by adding more indicators and modules for CBS in the very low epidemiological stratum.
Subject(s)
Health Information Systems , Malaria , Humans , Tanzania/epidemiology , Malaria/epidemiology , Health Facilities , ElectronicsABSTRACT
High-throughput Plasmodium genomic data is increasingly useful in assessing prevalence of clinically important mutations and malaria transmission patterns. Understanding parasite diversity is important for identification of specific human or parasite populations that can be targeted by control programmes, and to monitor the spread of mutations associated with drug resistance. An up-to-date understanding of regional parasite population dynamics is also critical to monitor the impact of control efforts. However, this data is largely absent from high-burden nations in Africa, and to date, no such analysis has been conducted for malaria parasites in Tanzania countrywide. To this end, over 1,000 P. falciparum clinical isolates were collected in 2017 from 13 sites in seven administrative regions across Tanzania, and parasites were genotyped at 1,800 variable positions genome-wide using molecular inversion probes. Population structure was detectable among Tanzanian P. falciparum parasites, approximately separating parasites from the northern and southern districts and identifying genetically admixed populations in the north. Isolates from nearby districts were more likely to be genetically related compared to parasites sampled from more distant districts. Known drug resistance mutations were seen at increased frequency in northern districts (including two infections carrying pfk13-R561H), and additional variants with undetermined significance for antimalarial resistance also varied by geography. Malaria Indicator Survey (2017) data corresponded with genetic findings, including average region-level complexity-of-infection and malaria prevalence estimates. The parasite populations identified here provide important information on extant spatial patterns of genetic diversity of Tanzanian parasites, to which future surveys of genetic relatedness can be compared.
Subject(s)
Malaria, Falciparum , Plasmodium falciparum , Drug Resistance/genetics , Humans , Malaria, Falciparum/epidemiology , Molecular Probes , Plasmodium falciparum/genetics , Tanzania/epidemiologyABSTRACT
BACKGROUND: Tanzania started implementing single screening and treatment (SST) for all pregnant women attending their first antenatal care (ANC) visits in 2014, using malaria rapid diagnostic tests (RDTs) and treating those who test positive according to the national guidelines. However, there is a paucity of data to show the acceptability of SST to both pregnant women and health care workers (HCWs), taking into consideration the shortage of workers and the added burden of this policy to the health system. This study assessed the perceptions and opinions of health service users and providers to determine the acceptability of SST policy. METHODS: Pregnant women and HCWs in eight health facilities in two districts of Lindi region (Kilwa and Lindi) were interviewed using semi-structured questionnaires with open and close-ended questions. Both qualitative and quantitative data were collected, including demographic characteristics, women's experience, their perception on SST and challenges they face when receiving services for malaria offered at ANC. Experience of HCWs regarding the implementation of SST as part of routine services and the challenges encountered when providing ANC services for malaria in pregnancy (MIP) were also assessed. RESULTS: Of the 143 pregnant women interviewed, 97% viewed testing favourably and would wish to be tested for malaria again, while 95% were satisfied with services and reasons for testing during the first ANC visit. Nearly all (99%) would recommend their fellow pregnant women to be tested for malaria and all women recommended that the Ministry of Health should continue the SST strategy. This was despite the fact that 76% of the women experienced pain and 16% had anxiety as a result of finger prick. Sixteen HCWs (mostly nurses) were interviewed; they also viewed SST implementation favourably and reported feeling empowered to use RDTs for malaria screening. The main challenge identified by HCWs was that nurses are not allowed to prescribe anti-malarials to women who test positive and need to refer them to the outpatient department for treatment. CONCLUSION: SST was considered an acceptable approach to control MIP by HCWs and pregnant women, and they recommended the continuation of the policy. In addition, consideration should be given to implementing a task-shifting policy to allow nurses to dispense anti-malarials to pregnant women.
Subject(s)
Antimalarials/therapeutic use , Health Facilities/statistics & numerical data , Health Policy , Malaria/prevention & control , Patient Acceptance of Health Care/statistics & numerical data , Pregnancy Complications, Parasitic/prevention & control , Adolescent , Adult , Female , Humans , Mass Screening , Middle Aged , Pregnancy , Pregnant Women , Prenatal Care , Tanzania , Young AdultABSTRACT
BACKGROUND: Over the past two decades, Zanzibar substantially reduced malaria burden. As malaria decreases, sustainable improvements in control interventions may increasingly depend on accurate knowledge of malaria risk factors to further target interventions. This study aimed to investigate the risk factors associated with malaria infection in Zanzibar. METHODS: Surveillance data from Zanzibar's Malaria Case Notification system from August 2012 and December 2019 were analyzed. This system collects data on malaria cases passively detected and reported by all health facilities (index cases), and household-based reactive case detection (RCD) activities linked to those primary cases. All members of households of the index cases were screened for malaria using a malaria rapid diagnostic test (RDT). Individuals with a positive RDT were treated with artemisinin-based combination therapy. Univariate and multivariate logistic regression analyses were done to investigate the association between RDT positivity among the household members and explanatory factors with adjustment for seasonality and clustering at Shehia level. RESULTS: A total of 30,647 cases were reported of whom household RCD was completed for 21,443 (63%) index case households and 85,318 household members tested for malaria. The findings show that younger age (p-value for trend [Ptrend] < 0.001), history of fever in the last 2 weeks (odds ratio [OR] = 35.7; 95% CI 32.3-39.5), travel outside Zanzibar in the last 30 days (OR = 2.5; 95% CI 2.3-2.8) and living in Unguja (OR = 1.2; 95% CI 1.0-1.5) were independently associated with increased odds of RDT positivity. In contrast, male gender (OR=0.8; 95% CI 0.7-0.9), sleeping under an LLIN the previous night (OR = 0.9; 95% CI 0.7-0.9), having higher household net access (Ptrend < 0.001), and living in a household that received IRS in the last 12 months (OR = 0.8; 95% CI 0.7-0.9) were independently associated with reduced odds of RDT positivity. A significant effect modification of combining IRS and LLIN was also noted (OR = 0.7; 95% CI 0.6-0.8). CONCLUSIONS: The findings suggest that vector control remains an important malaria prevention intervention: they underscore the need to maintain universal access to LLINs, the persistent promotion of LLIN use, and application of IRS. Additionally, enhanced behavioural change and preventive strategies targeting children aged 5-14 years and travellers are needed.
Subject(s)
Antimalarials/pharmacology , Artemisinins/pharmacology , Diagnostic Tests, Routine/statistics & numerical data , Malaria/epidemiology , Malaria/prevention & control , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Cross-Sectional Studies , Drug Combinations , Female , Humans , Infant , Infant, Newborn , Malaria/parasitology , Male , Middle Aged , Risk Factors , Tanzania/epidemiology , Young AdultABSTRACT
BACKGROUND: In areas of high transmission, malaria in pregnancy (MiP) primarily causes asymptomatic infections; these infections nonetheless increase the risk of adverse maternal and fetal outcomes. In 2014, Tanzania initiated a single screening and treatment (SST) strategy for all pregnant women at their first antenatal care (ANC) visit using malaria rapid diagnostic tests (RDT) for surveillance purposes. However, there is paucity of data on the effectiveness of SST in the prevention of MiP. The objective of this study was to estimate the number of asymptomatic infections among pregnant women detected by SST, which would have been missed in the absence of the policy. METHODS: Data from pregnant women attending their first ANC visits between October 2017 and June 2018, including gestational age, history of fever, and RDT results, were abstracted from ANC registers in eight health centres in two randomly selected districts, Kilwa and Lindi, in Lindi Region. The proportion of symptomatic (with history of fever in the past 48 h) and asymptomatic pregnant women with positive RDTs were calculated and stratified by trimester (first, second and third). The study areas were categorized as low transmission with prevalence < 10% or moderate/high with ≥ 10%. RESULTS: Over the study period, 1,845 women attended their first ANC visits; 22.1% were in the first trimester (< 12 weeks gestation age). Overall 15.0% of the women had positive RDTs, and there was a trend towards higher malaria prevalence in the first (15.9%) and second (15.2%) trimesters, compared to the third (7.1%), although the differences were not statistically significant (p = 0.07). In total, 6.9% of women reported fever within the past 48 h and, of these, 96.1% were RDT positive. For every 100 pregnant women in the moderate/high and low transmission areas, SST identified 60 and 26 pregnant women, respectively, with asymptomatic infections that would have otherwise been missed. Among the 15.9% of women detected in the first trimester, 50.7% were asymptomatic. CONCLUSION: In areas of moderate/high transmission, many infected women were asymptomatic, and would have been missed in the absence of SST. The benefits on maternal and fetal birth outcomes of identifying these infections depend heavily on the protection afforded by treatment, which is likely to be greatest for women presenting in the first trimester when intermittent preventive treatment (IPTp) with sulfadoxine-pyrimethamine (SP) is contraindicated, and in areas with high SP resistance, such as most parts of Tanzania. An evaluation of the impact and cost-effectiveness of SST across different transmission strata is warranted.
Subject(s)
Antimalarials/therapeutic use , Diagnostic Tests, Routine/statistics & numerical data , Malaria/prevention & control , Mass Screening/statistics & numerical data , Pregnancy Complications, Parasitic/prevention & control , Prenatal Care/methods , Female , Humans , Pregnancy , TanzaniaABSTRACT
BACKGROUND: Egypt ranks fifth for the burden of viral hepatitis worldwide. As part of Egypt's renewed national strategy for the elimination of viral hepatitis, surveillance for acute viral hepatitis (AVH) was re-established during 2014-2017 to describe the current epidemiology and associated risk factors, and changes from surveillance conducted during 2001-2004. METHODS: Patients with suspected AVH were enrolled, completed a questionnaire, and provided blood for testing for hepatitis viruses A (HAV), B (HBV), C (HCV), D, and E (HEV) infections by enzyme-linked immunosorbent assay. Odds ratios and Chi2 were used to detect differences between hepatitis types by patient characteristics and exposures. Newcombe-Wilson method was used to compare results between surveillance periods 2001-2004 and 2014-2017. RESULTS: Between 2014 and 2017, among 9321 patients enrolled, 8362 (89.7%) had one or more markers of AVH including 7806 (93.4%) HAV, 252 (3.0%) HCV, 238 (2.8%) HBV, and 31 (0.4%) HEV infection. HAV infection occurred most commonly among children < 16 years age, while HBV infection occurred among ages 16-35 years and HCV infection in ages greater than 45 years. Healthcare-associated exposures were significantly associated with HBV and HCV infections compared to HAV infection including receiving therapeutic injections, surgery, wound suture, or urinary catheter and IV line insertions, while significant lifestyle exposures included exposure to blood outside the healthcare system, IV drug use, or incarceration. Exposures significantly associated with HAV infection were attending nursery or pre-school, contact with person attending nursery or pre-school, having meals outside the home, or contact with HAV case. Compared with AVH surveillance during 2001-2004, there was a significant increase in the proportion of HAV infections from 40.2 to 89.7% (RR = 2.3) with corresponding reductions in the proportions of HBV and HCV infections from 30.0 to 2.8% (RR = 0.1) and 29.8 to 3.0% (RR = 0.1), respectively. CONCLUSIONS: Healthcare-associated exposures were significantly association with and remain the greatest risk for HBV and HCV infections in Egypt. Additional studies to evaluate factors associated with the reductions in HBV and HCV infections, and cost effectiveness of routine HAV immunization might help Egypt guide and evaluate control measures.
Subject(s)
Hepatitis A/epidemiology , Hepatitis B/epidemiology , Hepatitis C/epidemiology , Infection Control/trends , Sentinel Surveillance , Acute Disease , Adolescent , Adult , Aged , Aged, 80 and over , Child , Child, Preschool , Egypt/epidemiology , Female , Hepatitis, Viral, Human/classification , Hepatitis, Viral, Human/epidemiology , Humans , Infant , Infection Control/methods , Male , Middle Aged , Risk , Risk Factors , Risk Reduction Behavior , Young AdultABSTRACT
On March 30, 2014, the Ministry of Health and Social Welfare (MOHSW) of Liberia alerted health officials at Firestone Liberia, Inc. (Firestone) of the first known case of Ebola virus disease (Ebola) inside the Firestone rubber tree plantation of Liberia. The patient, who was the wife of a Firestone employee, had cared for a family member with confirmed Ebola in Lofa County, the epicenter of the Ebola outbreak in Liberia during March-April 2014. To prevent a large outbreak among Firestone's 8,500 employees, their dependents, and the surrounding population, the company responded by 1) establishing an incident management system, 2) instituting procedures for the early recognition and isolation of Ebola patients, 3) enforcing adherence to standard Ebola infection control guidelines, and 4) providing differing levels of management for contacts depending on their exposure, including options for voluntary quarantine in the home or in dedicated facilities. In addition, Firestone created multidisciplinary teams to oversee the outbreak response, address case detection, manage cases in a dedicated unit, and reintegrate convalescent patients into the community. The company also created a robust risk communication, prevention, and social mobilization campaign to boost community awareness of Ebola and how to prevent transmission. During August 1-September 23, a period of intense Ebola transmission in the surrounding areas, 71 cases of Ebola were diagnosed among the approximately 80,000 Liberians for whom Firestone provides health care (cumulative incidence = 0.09%). Fifty-seven (80%) of the cases were laboratory confirmed; 39 (68%) of these cases were fatal. Aspects of Firestone's response appear to have minimized the spread of Ebola in the local population and might be successfully implemented elsewhere to limit the spread of Ebola and prevent transmission to health care workers (HCWs).
Subject(s)
Disease Outbreaks/prevention & control , Hemorrhagic Fever, Ebola/prevention & control , Community Integration , Contact Tracing , Health Personnel , Hemorrhagic Fever, Ebola/epidemiology , Humans , Liberia/epidemiology , Occupational Diseases/prevention & control , SurvivorsABSTRACT
The current Ebola virus disease (Ebola) epidemic in West Africa is unprecedented in size and duration. Since the outbreak was recognized in March 2014, the World Health Organization (WHO) has reported 17,145 cases with 6,070 deaths, primarily in Guinea, Liberia, and Sierra Leone. Combined data show a case-fatality rate of approximately 70% in patients with a recorded outcome; a 30% survival rate means that thousands of patients have survived Ebola. An important component of a comprehensive Ebola response is the reintegration of Ebola survivors into their communities.
Subject(s)
Community Integration , Epidemics , Hemorrhagic Fever, Ebola/epidemiology , Hemorrhagic Fever, Ebola/therapy , Survivors , Adolescent , Adult , Child , Child, Preschool , Female , Humans , Infant , Liberia/epidemiology , Male , Middle Aged , Program Evaluation , Survivors/statistics & numerical data , Young AdultABSTRACT
The US Department of Defense continues to deploy military assets for disaster relief and humanitarian actions around the world. These missions, carried out through geographically located Combatant Commands, represent an evolving role the US military is taking in health diplomacy, designed to enhance disaster preparedness and response capability. Oceania is a unique case, with most island nations experiencing "acute-on-chronic" environmental stresses defined by acute disaster events on top of the consequences of climate change. In all Pacific Island nation-states and territories, the symptoms of this process are seen in both short- and long-term health concerns and a deteriorating public health infrastructure. These factors tend to build on each other. To date, the US military's response to Oceania primarily has been to provide short-term humanitarian projects as part of Pacific Command humanitarian civic assistance missions, such as the annual Pacific Partnership, without necessarily improving local capacity or leaving behind relevant risk-reduction strategies. This report describes the assessment and implications on public health of large-scale humanitarian missions conducted by the US Navy in Oceania. Future opportunities will require the Department of Defense and its Combatant Commands to show meaningful strategies to implement ongoing, long-term, humanitarian activities that will build sustainable, host nation health system capacity and partnerships. This report recommends a community-centric approach that would better assist island nations in reducing disaster risk throughout the traditional disaster management cycle and defines a potential and crucial role of Department of Defense's assets and resources to be a more meaningful partner in disaster risk reduction and community capacity building.
Subject(s)
Altruism , Disaster Planning , Disasters , Naval Medicine , Humans , International Cooperation , Oceania , Ships , United StatesABSTRACT
Tanzania is undergoing an epidemiological transition for malaria transmission with some areas of the country having <10% (hypoendemic) and other areas 10% - 50% malaria prevalence (mesoendemic). It is not known whether there is a difference in the quality of malaria case management based on endemicity in Tanzania mainland. We examined the influence of endemicity on the quality of malaria case management at health facilities. We conducted a cross-sectional analysis of 1713 health facilities in Tanzania mainland, using data collected by the National Malaria Control Program through an assessment tool to evaluate quality of malaria case management. The data was gathered from September 2017 to December 2018. Using standard quality factors, mean scores from facilities in the different endemicity regions were compared by a Student's t-test. Simple and multiple linear regression analyses were performed to determine the association between facility performance (score) and endemicity (mesoendemic vs. hypoendemic). Facilities in mesoendemic regions scored higher than those in hypoendemic regions on the overall quality of services [difference in mean scores ([Formula: see text]) = 2.52; (95% Confidence Interval (CI) 1.12, 3.91)], site readiness [[Formula: see text] = 2.97; (95% CI 1.30, 4.61)], availability of malaria reference materials [[Formula: see text] = 4.91; (95% CI 2.05, 7.76)], availability of Health Management Information System tools [[Formula: see text] = 5.86; (95% CI 3.80, 7.92)] and patient satisfaction [[Formula: see text] = 6.61; (95% CI 3.75, 9.48)]. Predictors associated with lower facility scores included; being located in a hypoendemic region [ß: -2.49; (95% CI -3.83, -1.15)] and urban area [ß: -3.84; (95% CI -5.60, -2.08)]. These findings highlight the differences in quality of malaria case management based on endemicity, but there is still a need to target improvement efforts in underperforming facilities, regardless of endemicity.
ABSTRACT
Zanzibar has made significant progress toward malaria elimination, but recent stagnation requires novel approaches. We developed a highly multiplexed droplet digital PCR (ddPCR)-based amplicon sequencing method targeting 35 microhaplotypes and drug-resistance loci, and successfully sequenced 290 samples from five districts covering both main islands. Here, we elucidate fine-scale Plasmodium falciparum population structure and infer relatedness and connectivity of infections using an identity-by-descent (IBD) approach. Despite high genetic diversity, we observe pronounced fine-scale spatial and temporal parasite genetic structure. Clusters of near-clonal infections on Pemba indicate persistent local transmission with limited parasite importation, presenting an opportunity for local elimination efforts. Furthermore, we observe an admixed parasite population on Unguja and detect a substantial fraction (2.9%) of significantly related infection pairs between Zanzibar and the mainland, suggesting recent importation. Our study provides a high-resolution view of parasite genetic structure across the Zanzibar archipelago and provides actionable insights for prioritizing malaria elimination efforts.
Subject(s)
Malaria, Falciparum , Plasmodium falciparum , Humans , Plasmodium falciparum/genetics , Malaria, Falciparum/epidemiology , Malaria, Falciparum/prevention & control , Malaria, Falciparum/parasitology , Tanzania/epidemiology , Drug Resistance , Polymerase Chain ReactionABSTRACT
Testing and treating asymptomatic populations have the potential to reduce the population's parasite reservoir and reduce malaria transmission. Zanzibar's malaria case notification (MCN) platform collects detailed sociodemographic and epidemiological data from all confirmed malaria cases to inform programmatic decision-making. We describe the design and operationalization process of the platform and other malaria surveillance resources that are enabling Zanzibar's progress toward malaria elimination.The MCN platform consists of an interactive short message service (SMS) system for case notification, a software application for Android mobile devices, a visual question set and workflow manager, a back-end database server, and a web browser-based application for data analytics, configuration, and management. Malaria case data were collected from August 2012 to December 2021 and reported via SMS from all public and private health facilities to a central database and then to district malaria surveillance officers' mobile devices. Data included patient names, shehia (administrative area), and date of diagnosis, enabling officers to track patients, ideally within 24 hours of reporting. Patients' household members were tested for malaria using conventional rapid diagnostic tests (RDTs). Treatment using artemisinin-based combination therapy was provided for persons testing positive.Between 2012 and 2021, a total of 48,899 index malaria cases were confirmed at health facilities, 22,152 (45.3%) within 24 hours of reporting; 41,886 (85.7%) cases were fully investigated and followed up to the household level. A total of 111,811 additional household members were tested with RDTs, of whom 10,602 (9.5%) were malaria positive.The MCN platform reports malaria case data in near real time, enabling prompt follow-up of index cases and prompt testing and treatment of members in index case households. Along with routine testing and treatment and other preventive interventions, the MCN platform is foundational to the programmatic efforts in further reducing malaria and ultimately eliminating autochthonous malaria transmission in Zanzibar.
Subject(s)
Antimalarials , Malaria , Humans , Antimalarials/therapeutic use , Tanzania/epidemiology , Malaria/epidemiology , Malaria/prevention & control , Combined Modality Therapy , Family CharacteristicsABSTRACT
BACKGROUND: Rabies causes an acute fatal encephalomyelitis in most mammals following infection with rhabdovirus of the genus Lyssavirus. Little is known about rabies virus infection in species of New World non-human Primates (NHP). To investigate the suitability of the owl monkey Aotus nancymaae asissue sections examined were unremarkable for inflammation or other histologic signs of rabies a viable animal model for rabies virus candidate vaccine testing, we used clinical presentation, serology, viral isolation, and PCR to evaluate the incubation period, immunity, and pathogenesis of infected animals. We tested the hypothesis that no viremic state exists for rabies virus. METHODS: Eight monkeys divided into two equal groups were inoculated intramuscularly either in the neck or footpad with 105 pfu of rabies virus (Pasteur/V-13R) and observed for >130 days. Oral and blood samples were collected and analyzed. RESULTS: Two monkeys inoculated in the neck displayed classic paralytic rabies. The mean incubation period was 11.5 days. The average maximum IgG response (antibody titer >0.200 O.D.) was achieved at day 10.0 and 62.3 in the clinical rabies and non-clinical rabies cases, respectively (p = 0.0429). No difference in IgM or IgG time to seroconversion or average maximum IgM level was observed between neck versus footpad inoculation groups. No viremia or viral shedding was detected by PCR or viral isolation during the observation period, including within the two symptomatic animals three days after disease onset. Tissue sections examined were unremarkable for inflammation or other histologic signs of rabies within the asymptomatic animal. Similarly none of the brain sections exhibited immunoreactivity for rabies virus antibody. DISCUSSION: This study demonstrates there is no difference in time to immune response between inoculation sites and distance to the brain; however, immune response tends to be more rapid in cases of clinically apparent disease and prolonged in cases infected at sites further from the brain. CONCLUSIONS: Our findings support the hypothesis that a viremic state for rabies does not exist in the New World Monkey, Aotus nancymaae, and it appears that this species may be refractory to infection. The species does provide a suitable model to assess post infection immune responses. Additional studies that address the limitations of sample size, length of observation, and lack of measurable infection should be conducted.
Subject(s)
Aotidae/virology , Monkey Diseases/virology , Rabies virus , Rabies/veterinary , Viremia/veterinary , Animals , Antibodies, Viral/immunology , Disease Susceptibility , Female , Immunoglobulin G/immunology , Immunoglobulin M/immunology , Monkey Diseases/diagnosis , Rabies virus/genetics , Rabies virus/immunology , Viremia/virologyABSTRACT
BACKGROUND: More timely estimates of malaria prevalence are needed to inform optimal control strategies and measure progress. Since 2014, Tanzania has implemented nationwide malaria screening for all pregnant women within the antenatal care system. We aimed to compare malaria test results during antenatal care to two population-based prevalence surveys in Tanzanian children aged 6-59 months to examine their potential in measuring malaria trends and progress towards elimination. METHODS: Malaria test results from pregnant women screened at their first antenatal care visits at health-care facilities (private and public) in all 184 districts of Tanzania between Jan 1, 2014, and Dec 31, 2017, were collected from the Health Management Information Systems and District Health Information System 2. We excluded facilities with no recorded antenatal care attendees during the time period. We standardised results to account for testing uptake and weighted them by the timing of two population-based surveys of childhood malaria prevalence done in 2015-16 (Demographic and Health Survey) and 2017 (Malaria Indicator Survey). We assessed regional-level correlation using Spearman's coefficient and assessed the consistency of monthly district-level prevalence ranking using Kendall's correlation coefficient. FINDINGS: Correlation between malaria prevalence at antenatal care and among children younger than 5 years was high (r≥0·83 for both surveys), although declines in prevalence at antenatal care were generally smaller than among children. Consistent heterogeneity (p<0·05) in antenatal care prevalence at the district level was evident in all but one region (Kilimanjaro). Data from antenatal care showed declining prevalence in three regions (Arusha, Kilimanjaro, and Manyara) where surveys estimated zero prevalence. INTERPRETATION: Routine antenatal care-based screening can be used to assess heterogeneity in transmission at finer resolution than population-based surveys, and provides sample sizes powered to detect changes, notably in areas of low transmission where surveys lack power. Declines in prevalence at antenatal care might lag behind those among children, highlighting the value of monitoring burden and continuing prevention efforts among pregnant women as transmission declines. The pregnancy-specific benefits and cost-effectiveness of antenatal care-based screening remain to be assessed. FUNDING: None.
Subject(s)
Malaria/epidemiology , Mass Screening/statistics & numerical data , Pregnancy Complications, Parasitic/epidemiology , Prenatal Care/statistics & numerical data , Cross-Sectional Studies , Female , Health Facilities , Humans , Pregnancy , Prevalence , Tanzania/epidemiology , Young AdultABSTRACT
BACKGROUND: Scientific publication in academic literature is a key venue in which the U.S. Department of Defense's Global Emerging Infections Surveillance and Response System (GEIS) program disseminates infectious disease surveillance data. Bibliometric analyses are tools to evaluate scientific productivity and impact of published research, yet are not routinely used for disease surveillance. Our objective was to incorporate bibliometric indicators to measure scientific productivity and impact of GEIS-funded infectious disease surveillance, and assess their utility in the management of the GEIS surveillance program. METHODS: Metrics on GEIS program scientific publications, project funding, and countries of collaborating institutions from project years 2006 to 2012 were abstracted from annual reports and program databases and organized by the six surveillance priority focus areas: respiratory infections, gastrointestinal infections, febrile and vector-borne infections, antimicrobial resistance, sexually transmitted infections, and capacity building and outbreak response. Scientific productivity was defined as the number of scientific publications in peer-reviewed literature derived from GEIS-funded projects. Impact was defined as the number of citations of a GEIS-funded publication by other peer-reviewed publications, and the Thomson Reuters 2-year journal impact factor. Indicators were retrieved from the Web of Science and Journal Citation Report. To determine the global network of international collaborations between GEIS partners, countries were organized by the locations of collaborating institutions. RESULTS: Between 2006 and 2012, GEIS distributed approximately US $330 million to support 921 total projects. On average, GEIS funded 132 projects (range 96-160) with $47 million (range $43 million-$53 million), annually. The predominant surveillance focus areas were respiratory infections with 317 (34.4%) projects and $225 million, and febrile and vector-borne infections with 274 (29.8%) projects and $45 million. The number of annual respiratory infections-related projects peaked in 2006 and 2009. The number of febrile and vector-borne infections projects increased from 29 projects in 2006 to 58 in 2012. There were 651 articles published in 147 different peer-reviewed journals, with an average Thomson Reuters 2-year journal impact factor of 4.2 (range 0.3-53.5). On average, 93 articles were published per year (range 67-117) with $510,000 per publication. Febrile and vector-borne, respiratory, and gastrointestinal infections had 287, 167, and 73 articles published, respectively. Of the 651 articles published, 585 (89.9%) articles were cited at least once (range 1-1,045). Institutions from 90 countries located in all six World Health Organization regions collaborated with surveillance projects. CONCLUSIONS: These findings summarize the GEIS-funded surveillance portfolio between 2006 and 2012, and demonstrate the scientific productivity and impact of the program in each of the six disease surveillance priority focus areas. GEIS might benefit from further financial investment in both the febrile and vector-borne and sexually transmitted infections surveillance priority focus areas and increasing peer-reviewed publications of surveillance data derived from respiratory infections projects. Bibliometric indicators are useful to measure scientific productivity and impact in surveillance systems; and this methodology can be utilized as a management tool to assess future changes to GEIS surveillance priorities. Additional metrics should be developed when peer-reviewed literature is not used to disseminate noteworthy accomplishments.