Spatial Markov matrices for measuring the spatial dependencies of an epidemiological spread : case Covid'19 Madagascar.

BACKGROUND: This article applies a variant of the Markov chain that explicitly incorporates spatial effects. It is an extension of the Markov class allowing a more complete analysis of the spatial dimensions of transition dynamics. The aim is to provide a methodology for applying the explicit model to spatial dependency analysis. METHODS: Here, the question is to study and quantify whether neighborhood context affects transitional dynamics. Rather than estimating a homogeneous law, the model requires the estimation of k transition laws each dependent on spatial neighbor state. This article used published data on confirmed cases of Covid'19 in the 22 regions of Madagascar. These data were discretized to obtain a discrete state of propagation intensity. RESULTS: The analysis gave us the transition probabilities between Covid'19 intensity states knowing the context of neighboring regions, and the propagation time laws knowing the spatial contexts. The results showed that neighboring regions had an effect on the propagation of Covid'19 in Madagascar. CONCLUSION: After analysis, we can say that there is spatial dependency according to these spatial transition matrices.

Implementation of the WHO Tricycle protocol for surveillance of extended-spectrum ß-lactamase producing Escherichia coli in humans, chickens, and the environment in Madagascar: a prospective genomic epidemiology study.

BACKGROUND: Antimicrobial resistance (AMR) is a major public health threat, affecting not only people but also animals and the environment. The One Health dimension of AMR is well known; however, data are lacking on the circulation of resistance-conferring genes, particularly in low-income countries. In 2017, WHO proposed a protocol called Tricycle, focusing on extended-spectrum ß-lactamase (ESBL)-Escherichia coli surveillance in the three sectors (humans, animals, and the environment). We implemented Tricycle in Madagascar to assess ESBL-E coli prevalence and describe intrasector and intersector circulation of ESBL-E coli and plasmids. METHODS: In this prospective study, we collected blood culture data from hospitalised patients with a suspected bloodstream infection processed from May 1, 2018, to April 30, 2019, and rectal swabs from healthy pregnant women from July 30, 2018, to April 27, 2019, both from three hospitals in Antananarivo, Madagascar; and caeca from farm chickens and surface waters from the Ikopa river, wastewater, and slaughterhouse effluents in the Antananarivo area, Madagascar, from April 9, 2018, to April 30, 2019. All samples were tested for ESBL-E coli. The genomes of all isolates were sequenced using a short-read method on NextSeq 500 and NovaSeq 6000 platforms (Illumina, San Diego, CA, USA) and those carrying plasmid replicons using an additional long-read method on a MinION platform (Oxford Nanopore Technologies, Oxford, UK). We characterised genomes of isolated strains (sequence type, resistance and virulence gene content, and plasmid replicons). We then compared isolates using the variant calling method (single-nucleotide polymorphism). FINDINGS: Data from 1056 blood cultures were collected and 289 pregnant women, 246 chickens, and 28 surface waters were sampled. Of the blood cultures, 18 contained E coli, of which seven (39%) were ESBL. ESBL-E coli was present in samples from 86 (30%) of 289 pregnant women, 140 (57%) of 246 chickens, and 28 (100%) of 28 surface water samples. The wet season (November to April) was associated with higher rates of carriage in humans (odds ratio 3·08 [1·81-5·27]) and chickens (2·79 [1·65-4·81]). Sequencing of 277 non-duplicated isolates (82 from pregnant women, 118 from chickens, and 77 from environmental samples) showed high genetic diversity (90 sequence types identified) with sector-specific genomic features. Single nucleotide polymorphism (SNP) analysis revealed that 169 (61%) of 277 isolates grouped into 44 clusters (two or more isolates) of closely related isolates (<40 SNPs), of which 24 clusters contained isolates from two sectors and five contained isolates from all three sectors. ESBL genes were all blaCTX-M variants (215 [78%] of 277 being blaCTX-M-15) and were located on a plasmid in 113 (41%) of 277 isolates. These ESBL-carrying plasmids were mainly IncF (63 [55%] of 114; one strain carried two plasmids) and IncY (42 [37%] of 114). The F31/36:A4:B1 (n=13) and F-:A-:B53 (n=8) pMLST subtypes, and the IncY plasmids, which were all highly conserved, were observed in isolates of differing genetic backgrounds from all sectors and were transferable in vitro by conjugation. INTERPRETATION: Despite sector-specific population structures, both ESBL-E coli strains and plasmids are circulating among humans, chickens, and the environment in Antananarivo, Madagascar. The Tricycle protocol can be implemented in a low-income country and represents a powerful tool for investigating dissemination of AMR from a One Health perspective. FUNDING: Fondation Mérieux and INSERM, Université Paris Cité.

Strengthening disease surveillance capacity at national level across five countries: a qualitative study.

OBJECTIVES: Disease surveillance is an essential component of public health and a core function of National Public Health Institutes (NPHIs), including to better prepare and respond to infectious diseases outbreaks. Strengthening NPHIs in their efforts to establish and maintain efficient surveillance systems is an opportunity to ensure future outbreak preparedness and response; yet, guidance on how to increase and prioritise capacity building efforts is limited. This study sought to investigate approaches to capacity building and training for disease surveillance at national level and understand the potential role of NPHIs. STUDY DESIGN: Qualitative study. METHODS: This is a qualitative study, based on a literature review and interviews undertaken between June and November 2022. Fifty seven in-depth interviews were conducted in five countries: Côte d'Ivoire, Ecuador, Madagascar, Namibia, and the Kingdom of Saudi Arabia. Participants included a range of professionals from government, NPHIs, academic institutions and the private sector. Interviews were thematically analysed. RESULTS: Selected countries varied in terms of their disease surveillance capacities, as well as in the structure of their surveillance systems and decision-making. Research identified shared priority areas for action at national level, identifying common challenges and opportunities: 1) capacity building, here specifically the need for a training agenda at national level to ensure sustainability and guide donor funded training offers; 2) data tools and technology-to help decision-makers select the best software tool to address countries' identified need; 3) data sharing-the need for clear data sharing standards and norms for national to international data sharing; and 4) genomic sequencing-the need for national genomic surveillance strategies and reporting guidelines. CONCLUSION: Addressing challenges and using opportunities to strengthen disease surveillance at national level is an important step to build capacity in this area and to help prevent future epidemic and pandemics globally. The findings of this study help decision-makers to identify priority areas for capacity building and understand the potential role and significance of NPHIs.

Place of residence and blood sugar testing practices among men: insights from the 2021 Madagascar demographic and health survey.

BACKGROUND: In 2021, Madagascar had approximately 13,919 people living with diabetes, with 66.1% of cases being undiagnosed. The implication is that this population are at high risk of developing diabetes complications which will affect their quality of life. However, promoting the uptake of screening practices such as the blood glucose test among the asymptomatic population would offer a chance to reduce the prevalence of undiagnosed diabetes in the country. This study examined the association between place of residence and blood sugar testing practices among men in Madagascar. METHODS: Secondary data from the men recode file of the 2021 Madagascar Demographic and Health Survey (MDHS) was used. A sample of 9,035 were used for the analysis. Descriptive and multivariate analyses were performed in STATA version 14. The results are presented in adjusted odds ratio (AOR) with the corresponding 95% confidence interval. RESULTS: Only 5.83% reported to have ever had their blood glucose/sugar tested by a health professional. Residing in rural areas was associated in lower likelihood of undergoing a test to check one's blood sugar level [AOR = 0.23; 95%CI = 0.19-0.28] compared to those in urban areas. This association remained consistent even after adjusting for the effects of covariates [AOR = 0.67; 95%CI = 0.52-0.86]. CONCLUSION: We conclude that place of residence plays a significant role in influencing men's decision to test their blood glucose level. It is, therefore, imperative for the Madagascar Public Health Department to liaise with the government to bridge the rural-urban disparities in terms of accessibility to blood glucose testing services. Practically, this can be achieved by instituting community-based health services centers in the rural areas of Madagascar to mitigate the rural-urban disparities. Also, health education campaigns to raise men's awareness about the need to test their blood glucose level must necessarily target older men, those without formal education, those without health insurance, and men who have been diagnosed with hypertension.

Astroviruses in terrestrial Malagasy mammals.

Small terrestrial mammals are major hosts of infectious agents responsible for zoonotic diseases. Astroviruses (AstVs)-the cause of non-bacterial gastroenteritis mainly affecting young children-have been detected in a wide array of mammalian and avian host species. However, understanding the factors that influence AstV infection within and across hosts is limited. Here, we investigated the impact of land use changes on AstVs in terrestrial small mammals in rural northeastern Madagascar. We sampled 515 small mammals, representing seven endemic and four introduced species. Twenty-two positive samples were identified, all but one of which were found in the introduced species Mus musculus and Rattus rattus (family Muridae), with a positivity rate of 7.7% (6/78) and 5.6% (15/266), respectively. The non-introduced rodent case was from an endemic shrew-tenrec (family Tenrecidae). We found the highest positivity rate of AstVs infection in brushy regrowth (17.5%, 7/40) as compared to flooded rice fields (4.60%, 8/174), secondary forest (4.1%, 3/74), agroforest (3.6%, 1/28), village (2.61%, 3/115), and semi-intact forest (0%, 0/84). A phylogenetic analysis revealed an association between AstVs and their rodent host species. None of the viruses were phylogenetically related to AstVs previously described in Malagasy bats. This study supports AstV circulation in synanthropic animals in agricultural habitats of Madagascar and highlights the need to assess the spillover risk to human populations in rural areas.

Review of genotyping methods for Yersinia pestis in Madagascar.

BACKGROUND: Plague, a zoonotic disease caused by Yersinia pestis, was responsible for 3 historical human pandemics that killed millions of people. It remains endemic in rodent populations in Africa, Asia, North America, and South America but human plague is rare in most of these locations. However, human plague is still highly prevalent in Madagascar, which typically records a significant part of all annual global cases. This has afforded an opportunity to study contemporary human plague in detail using various typing methods for Y. pestis. AIM: This review aims to summarize the methods that have been used to type Y. pestis in Madagascar along with the major discoveries that have been made using these approaches. METHODS: Pubmed and Google Scholar were used to search for the keywords: "typing Yersinia pestis Madagascar," "evolution Yersinia pestis Madagascar," and "diversity Yersinia pestis Madagascar." Eleven publications were relevant to our topic and further information was retrieved from references cited in those publications. RESULTS: The history of Y. pestis typing in Madagascar can be divided in 2 periods: the pre-genomics and genomics eras. During the pre-genomics era, ribotyping, direct observation of plasmid content and plasmid restriction fragment length polymorphisms (RFLP) were employed but only revealed a limited amount of diversity among Malagasy Y. pestis strains. Extensive diversity only started to be revealed in the genomics era with the use of clustered regularly interspaced palindromic repeats (CRISPR), multiple-locus variable number tandem repeats (VNTR) analysis (MLVA), and single-nucleotide polymorphisms (SNPs) discovered from whole genome sequences. These higher-resolution genotyping methods have made it possible to highlight the distribution and persistence of genotypes in the different plague foci of Madagascar (Mahajanga and the Central and Northern Highlands) by genotyping strains from the same locations across years, to detect transfers between foci, to date the emergence of genotypes, and even to document the transmission of antimicrobial resistant (AMR) strains during a pneumonic plague outbreak. Despite these discoveries, there still remain topics that deserve to be explored, such as the contribution of horizontal gene transfer to the evolution of Malagasy Y. pestis strains and the evolutionary history of Y. pestis in Madagascar. CONCLUSIONS: Genotyping of Y. pestis has yielded important insights on plague in Madagascar, particularly since the advent of whole-genome sequencing (WGS). These include a better understanding of plague persistence in the environment, antimicrobial AMR and multi-drug resistance in Y. pestis, and the person-to-person spread of pneumonic plague. Considering that human plague is still a significant public health threat in Madagascar, these insights can be useful for controlling and preventing human plague in Madagascar and elsewhere, and also are relevant for understanding the historical pandemics and the possible use of Y. pestis as a biological weapon.

Post-exposure prophylaxis in leprosy (PEOPLE): a cluster randomised trial.

BACKGROUND: Post-exposure prophylaxis (PEP) using single-dose rifampicin reduces progression from infection with Mycobacterium leprae to leprosy disease. We compared effectiveness of different administration modalities, using a higher (20 mg/kg) dose of rifampicin-single double-dose rifampicin (SDDR)-PEP. METHODS: We did a cluster randomised study in 16 villages in Madagascar and 48 villages in Comoros. Villages were randomly assigned to four study arms and inhabitants were screened once a year for leprosy, for 4 consecutive years. All permanent residents (no age restriction) were eligible to participate and all identified patients with leprosy were treated with multidrug therapy (SDDR-PEP was provided to asymptomatic contacts aged ≥2 years). Arm 1 was the comparator arm, in which no PEP was provided. In arm 2, SDDR-PEP was provided to household contacts of patients with leprosy, whereas arm 3 extended SDDR-PEP to anyone living within 100 m. In arm 4, SDDR-PEP was offered to household contacts and to anyone living within 100 m and testing positive to anti-phenolic glycolipid-I. The main outcome was the incidence rate ratio (IRR) of leprosy between the comparator arm and each of the intervention arms. We also assessed the individual protective effect of SDDR-PEP and explored spatial associations. This trial is registered with ClinicalTrials.gov, NCT03662022, and is completed. FINDINGS: Between Jan 11, 2019, and Jan 16, 2023, we enrolled 109 436 individuals, of whom 95 762 had evaluable follow-up data. Our primary analysis showed a non-significant reduction in leprosy incidence in arm 2 (IRR 0·95), arm 3 (IRR 0·80), and arm 4 (IRR 0·58). After controlling for baseline prevalence, the reduction in arm 3 became stronger and significant (IRR 0·56, p=0·0030). At an individual level SDDR-PEP was also protective with an IRR of 0·55 (p=0·0050). Risk of leprosy was two to four times higher for those living within 75 m of an index patient at baseline. INTERPRETATION: SDDR-PEP appears to protect against leprosy but less than anticipated. Strong spatial associations were observed within 75 m of index patients. Targeted door-to-door screening around index patients complemented by a blanket SDDR-PEP approach will probably have a substantial effect on transmission. FUNDING: European and Developing Countries Clinical Trials Partnership. TRANSLATION: For the French translation of the abstract see Supplementary Materials section.

Dog ecology and rabies control including canine vaccination coverage: Impacts from a survey in Madagascar.

BACKGROUND: Rabies virus (RABV; species Lyssavirus rabies) is causing one of the oldest zoonotic diseases known to mankind, leading to fatal encephalomyelitis in animals and humans. Despite the existence of safe and effective vaccines to prevent the disease, an estimated 99% of human rabies deaths worldwide are caused by dog-mediated rabies with children at the highest risk of infection. Rabies has been endemic in Madagascar for over a century, yet there has been little research evaluating local knowledge and practices impacting on the rabies control and prevention. Thus, this study was undertaken to better understand the dog ecology including canine vaccine coverage and to assess knowledge and practices of dog owners and veterinarians. METHODOLOGY: A cross-sectional study was conducted among 123 dog-owning households in thirteen fokontanys in Mahajanga from July 4 to September 13, 2016. Single and multi-member dog-owning households in the study area on the day of the interview were eligible for inclusion and purposively selected with the support of a local guide. The survey included a household questionnaire capturing information on the dog's demographics, husbandry practices, knowledge and practices towards rabies and its control measures; the dog ecology questionnaire collected dog characteristics, vaccination status and husbandry practices. All households that reported a dog bite incident, were invited to participate in a dog bite questionnaire. In addition, direct observations of roaming dogs were conducted to assess dog population demographics and to document behavioural characteristics. Two veterinarians were purposively selected and took part in an interview during the survey period, providing information on rabies control activities, including dog-care practices in the area. Descriptive and inferential data analyses were performed using Epi Info version 7.1.5.0 (CDC Atlanta, USA). RESULTS: We recorded a total of 400 dogs, of which 338 (84.5%) were owned amongst 123 households. More than half (67.8%) of owned dogs were between 1 to 5 years old and 95.6% were kept for guarding purposes. 45% of the surveyed dogs had free access to roam outside the premises. The majority (85.4%) of dog owners were knowledgeable that a dog bite could potentially transmit RABV to humans. 19 dog bites were reported and of these 73.6% were caused by the owner's or a neighbour's dog. In 6 of the 19 cases, children between 7 and 15 years of age were the victims. Dog vaccination coverage against rabies was 34% among owned dogs. Of the participants aware of a veterinarian, the majority (55/82) indicated that they accessed veterinarian services at irregular intervals. The main obstacles to vaccinations cited by dog owners were limited financial resources and difficulty accessing veterinary care. CONCLUSION: This study contributes to enhanced understanding of the dog ecology including canine vaccine coverage as well as knowledge and practices of dog owners in Madagascar. Most dogs in the study area were accessible for preventive vaccination through their owners, however only one third of the investigated canine population was vaccinated against rabies. Concerted national efforts towards rabies prevention and control should aim to address financial challenges and access to veterinary services.

Survival within 12months after stroke in Madagascar.

The data on the long-term prognosis of stroke are scarce in Madagascar. Our objective was to determine survival within 12months after a stroke event. A longitudinal study was carried out on a hospital cohort of subjects with stroke in Mahajanga in western Madagascar. We included in the study all subjects admitted to adult emergencies at Mahajanga University Hospitals during the year 2019 and diagnosed with stroke. A follow-up by telephone call or by descent at the home of the patients was carried out after at least 12months from the onset of the disease. We analyzed in-hospital mortality and survival within 12months after the stroke. At the end of the study period, 144 stroke cases were retained. Strokes accounted for 5.07% of emergency admission causes. Male gender accounted for 51.4% of the population. The average age of the subjects was 60.7years. In-hospital mortality was 32.6%. Survival at 1month was 50%, at 3months 48.4%, and at 12months 43%. High blood pressure was found as a risk factor for stroke in 79.9% of patients, 76.5% of whom were undertreated. Stroke mortality was high in our population. Most of the deaths occurred during the first month. Improved prevention and care are needed in Madagascar.

Prevalence of pulmonary tuberculosis and HIV infections and risk factors associated to tuberculosis in detained persons in Antananarivo, Madagascar.

The incidence rate of tuberculosis in prisons is estimated to be 8 times greater than that in the general population in Madagascar. Our objectives were to estimate the prevalence of pulmonary tuberculosis and HIV infection among prisoners and to identify risk factors associated with tuberculosis. We conducted a cross-sectional study at the central prison of Antananarivo from March to July 2021. Individual male and female inmates aged ≥ 13 years who had lived in the prison for at least three months prior to the study period were included as participants. Acid-fast bacilli detection by microscopy and/or culture, an intradermal tuberculin test, a chest X-ray, and a rapid diagnostic orientation test for HIV were performed. Among 748 participants, 4 (0.5%) were confirmed to have pulmonary tuberculosis. Overall, 14 (1.9%) patients had "confirmed" or "probable" tuberculosis [0.90-2.84, 95% CI]. The proportion of participants with latent tuberculosis infection was 69.6% (517/743) based on a positive tuberculin test without clinical symptoms or radiography images indicating tuberculosis. Out of 745 HIV screening tests, three showed reactive results (0.4%). Age (OR = 4.4, 95% CI [1.4-14.0]) and prior tuberculosis treatment (or episodes) were found to be associated with confirmed and probable tuberculosis.

Identifying and characterizing high-risk populations in pilot malaria elimination districts in Madagascar: a mixed-methods study.

BACKGROUND: In Madagascar, the districts of Antsirabe II, Faratsiho and Antsiranana I have relatively low malaria incidence rates and have been selected by the National Malaria Control Programme for pilot elimination strategies. The districts have residual transmission despite increasing coverage and quality of malaria services. This study sought to identify priority subpopulations at highest risk for malaria and collect information on intervention preferences and methods that will inform subnational tailoring of malaria service delivery. METHODS: This mixed methods study employed (i) a quantitative malaria risk factor assessment in Antsirabe II and Faratsiho comprising a test-negative frequency matched case-control study and a qualitative risk factor assessment in Antsiranana I; and (ii) a qualitative formative assessment in all three districts. For the case-control study, a mixed effects logistic regression was used with age, sex and district included as fixed effects and health facility included as a random effect. The qualitative risk factor assessment used semi-structured interview guides and key informant interviews. For the qualitative formative assessment in the three districts, a summary report was generated following semi-structured interviews and focus group discussions with high-risk populations (HRPs) and stakeholders. RESULTS: In Antsirabe II and Faratsiho districts, rice agriculture workers, outdoor/manual workers, particularly miners, and those with jobs that required travel or overnight stays, especially itinerant vendors, had higher odds of malaria infection compared to other (non-rice) agricultural workers. In Antsiranana I, respondents identified non-rice farmers, mobile vendors, and students as HRPs. Risk factors among these groups included overnight stays and travel patterns combined with a lack of malaria prevention tools. HRPs reported treatment cost and distance to the health facility as barriers to care and expressed interest in presumptive treatment and involvement of gatekeepers or people who have influence over intervention access or participation. CONCLUSIONS: The study results illustrate the value of in-depth assessments of risk behaviours, access to services and prevention tools, surveillance and prevention strategies, and the involvement of gatekeepers in shaping subnational tailoring to reach previously unreached populations and address residual transmission in elimination settings.

Schistosome infection among pregnant women in the rural highlands of Madagascar: A cross-sectional study calling for public health interventions in vulnerable populations.

INTRODUCTION: Schistosomiasis is a parasitic infection highly prevalent in sub-Saharan Africa (SSA) with Madagascar being among the countries with highest burden of the disease worldwide. Despite WHO recommendations, suggesting treatment of pregnant women after the first trimester, this group is still excluded from Mass Drug Administration programs. Our study, had the objective to measure the prevalence of schistosome infection among pregnant women in Madagascar in order to inform public health policies for treatment in this vulnerable population. METHODS: Women were recruited for this cross-sectional study between April 2019 and February 2020 when attending Antenatal Care Services (ANCs) at one of 42 included Primary Health Care Centers. The urine-based upconverting reporter particle, lateral flow (UCP-LF) test detecting circulating anodic antigen was used for the detection of schistosome infections. To identify factors associated with the prevalence of schistosome infection crude and adjusted prevalence ratios and 95% CIs were estimated using mixed-effect Poisson regression. RESULTS: Among 4,448 participating women aged between 16 and 47 years, the majority (70.4%, 38 n = 3,133) resided in rural settings. Overall, the prevalence of schistosome infection was 55.9% (n = 2486, CI 95%: 53.3-58.5). A statistically significant association was found with age group (increased prevalence in 31-47 years old, compared to 16-20 years old (aPR = 1.15, CI 95%: 1.02-1.29) and with uptake of antimalaria preventive treatment (decreased prevalence, aPR = 0.85, CI 95%: 0.77-0.95). No other associations of any personal characteristics or contextual factors with schistosome infection were found in our multivariate regression analysis. DISCUSSION AND CONCLUSION: The high prevalence of schistosome infection in pregnant women supports the consideration of preventive schistosomiasis treatment in ANCs of the Malagasy highlands. We strongly advocate for adapting schistosomiasis programs in highly endemic contexts. This, would contribute to both the WHO and SDGs agendas overall to improving the well-being of women and consequently breaking the vicious cycle of poverty perpetuated by schistosomiasis.

Effects of an intervention program to improve mental health and epilepsy care in Madagascar.

BACKGROUND: Despite the high prevalence of mental disorders and epilepsy in low- and middle-income countries, nearly 80% of patients are not treated. In Madagascar, initiatives to improve access to epilepsy and mental health care, including public awareness and training of general practitioners (GPs), were carried out between 2013 and 2018. Our study's main objective was to assess the effectiveness of these initiatives, two to five years post-intervention. METHODS: This quasi-experimental study (intervention vs. control areas) included five surveys assessing: general population's Knowledge Attitudes and Practices (KAP), GPs' KAP , number of epilepsy and mental health consultations at different levels of the healthcare system, diagnostic accuracy, and treatments' availability. OUTCOMES: In the general population, KAP scores were higher in intervention areas for epilepsy (11.4/20 vs. 10.3/20; p = 0.003). For mental disorders, regardless of the area, KAP scores were low, especially for schizophrenia (1.1/20 and 0.1/20). Among GPs, KAP scores were higher in intervention areas for schizophrenia (6.0/10 vs. 4.5/10; p = 0.008) and epilepsy (6.9/10 vs. 6.2/10; p = 0.044). Overall, there was a greater proportion of mental health and epilepsy consultations in intervention areas (4.5% vs 2.3%). Although low, concordance between GPs' and psychiatrists' diagnoses was higher in intervention areas. There was a greater variety of anti-epileptic and psychotropic medications available in intervention areas. INTERPRETATION: This research has helped to better understand the effectiveness of initiatives implemented in Madagascar to improve epilepsy and mental health care and to identify barriers which will need to be addressed. FUNDING: Sanofi Global Health, as part of the Fight Against STigma Program.

Heterogeneity in elimination efforts could increase the risk of resurgence of lymphatic filariasis in Madagascar.

BACKGROUND: Progress in lymphatic filariasis (LF) elimination is spatially heterogeneous in many endemic countries, which may lead to resurgence in areas that have achieved elimination. Understanding the drivers and consequences of such heterogeneity could help inform strategies to reach global LF elimination goals by 2030. This study assesses whether differences in age-specific compliance with mass drug administration (MDA) could explain LF prevalence patterns in southeastern Madagascar and explores how spatial heterogeneity in prevalence and age-specific MDA compliance may affect the risk of LF resurgence after transmission interruption. METHODOLOGY: We used LYMFASIM model with parameters in line with the context of southeastern Madagascar and explored a wide range of scenarios with different MDA compliance for adults and children (40-100%) to estimate the proportion of elimination, non-elimination and resurgence events associated with each scenario. Finally, we evaluated the risk of resurgence associated with different levels of migration (2-6%) from surrounding districts combined with varying levels of LF microfilaria (mf) prevalence (0-24%) during that same study period. RESULTS: Differences in MDA compliance between adults and children better explained the observed heterogeneity in LF prevalence for these age groups than differences in exposure alone. The risk of resurgence associated with differences in MDA compliance scenarios ranged from 0 to 19% and was highest when compliance was high for children (e.g. 90%) and low for adults (e.g. 50%). The risk of resurgence associated with migration was generally higher, exceeding 60% risk for all the migration levels explored (2-6% per year) when mf prevalence in the source districts was between 9% and 20%. CONCLUSION: Gaps in the implementation of LF elimination programme can increase the risk of resurgence and undermine elimination efforts. In Madagascar, districts that have not attained elimination pose a significant risk for those that have achieved it. More research is needed to help guide LF elimination programme on the optimal strategies for surveillance and control that maximize the chances to sustain elimination and avoid resurgence.

Mixed methods to evaluate knowledge, attitudes and practices (KAP) towards rabies in central and remote communities of Moramanga district, Madagascar.

Control of dog-mediated rabies relies on raising awareness, access to post-exposure prophylaxis (PEP) and mass dog vaccination. To assess rabies awareness in Moramanga district, Madagascar, where rabies is endemic, two complementary quantitative and qualitative approaches were carried out in 2018. In the quantitative approach, a standardized questionnaire was administered to 334 randomized participants living in 170 households located less than 5 km from the anti-rabies treatment center (ARTC) located in Moramanga city (thereafter called the central area), and in 164 households located more than 15 km away from the ARTC in two rural communes (thereafter called the remote area). Logistic regression models were fitted to identify factors influencing knowledge and practice scores. The qualitative approach consisted in semi-structured interviews conducted with 28 bite victims who had consulted the ARTC, three owners of biting dogs, three ARTC staff and two local authorities. Overall, 15.6% (52/334) of households owned at least one dog. The dog-to-human ratio was 1:17.6. The central area had a significantly higher dog bite incidence (0.53 per 100 person-years, 95% CI: 0.31-0.85) compared to the remote area (0.22 per 100 person-years, 95% CI: 0.09-0.43) (p = 0.03). The care pathway following a bite depended on wound severity, how the dog was perceived and its owner's willingness to cover costs. Rabies vaccination coverage in dogs in the remote area was extremely low (2.4%). Respondents knew that vaccination prevented animal rabies but owners considered that their own dogs were harmless and cited access and cost of vaccine as main barriers. Most respondents were not aware of the existence of the ARTC (85.3%), did not know the importance of timely access to PEP (92.2%) or that biting dogs should be isolated (89.5%) and monitored. Good knowledge scores were significantly associated with having a higher socio-economic status (OR = 2.08, CI = 1.33-3.26) and living in central area (OR = 1.91, CI = 1.22-3.00). Good practice scores were significantly associated with living in central area (OR = 4.78, CI = 2.98-7.77) and being aware of the ARTC's existence (OR = 2.29, CI = 1.14-4.80). In Madagascar, knowledge on rabies was disparate with important gaps on PEP and animal management. Awareness campaigns should inform communities (i) on the importance of seeking PEP as soon as possible after an exposure, whatever the severity of the wound and the type of biting dog who caused it, and (ii) on the existence and location of ARTCs where free-of-charge PEP is available. They should also encourage owners to isolate and monitor the health of biting dogs. Above all, awareness and dog vaccination campaigns should be designed so as to reach the more vulnerable remote rural populations as knowledge, good practices and vaccination coverage were lower in these areas. They should also target households with a lower socio-economic status. If awareness campaigns are likely to succeed in improving access to ARTCs in Madagascar, their impact on prompting dog owners to vaccinate their own dogs seems more uncertain given the financial and access barriers. Therefore, to reach the 70% dog vaccination coverage goal targeted in rabies elimination programs, awareness campaigns must be combined with free-of-charge mass dog vaccination.

Socio-ecological risk factors associated with human flea infestations of rural household in plague-endemic areas of Madagascar.

Plague is a flea-borne fatal disease caused by the bacterium Yersinia pestis, which persists in rural Madagascar. Although fleas parasitizing rats are considered the primary vectors of Y. pestis, the human flea, Pulex irritans, is abundant in human habitations in Madagascar, and has been found naturally infected by the plague bacterium during outbreaks. While P. irritans may therefore play a role in plague transmission if present in plague endemic areas, the factors associated with infestation and human exposure within such regions are little explored. To determine the socio-ecological risk factors associated with P. irritans infestation in rural households in plague-endemic areas of Madagascar, we used a mixed-methods approach, integrating results from P. irritans sampling, a household survey instrument, and an observational checklist. Using previously published vectorial capacity data, the minimal P. irritans index required for interhuman bubonic plague transmission was modeled to determine whether household infestations were enough to pose a plague transmission risk. Socio-ecological risk factors associated with a high P. irritans index were then identified for enrolled households using generalized linear models. Household flea abundance was also modeled using the same set of predictors. A high P. irritans index occurred in approximately one third of households and was primarily associated with having a traditional dirt floor covered with a plant fiber mat. Interventions targeting home improvement and livestock housing management may alleviate flea abundance and plague risk in rural villages experiencing high P. irritans infestation. As plague-control resources are limited in developing countries such as Madagascar, identifying the household parameters and human behaviors favoring flea abundance, such as those identified in this study, are key to developing preventive measures that can be implemented at the community level.

A cross-sectional analysis of the effectiveness of a nutritional support programme for people with tuberculosis in Southern Madagascar using secondary data from a non-governmental organisation.

BACKGROUND: There is a strong, bi-directional link between tuberculosis (TB) and undernutrition: TB often causes undernutrition, and undernourished people are more likely to contract TB and experience worse outcomes. Globally, several TB nutritional support programmes exist; however, evidence on their effectiveness is limited and contested. This study evaluates the effect of a nutritional support programme implemented for people with TB in the Atsimo-Andrefana region, Madagascar in 2022. Within this programme, undernourished people with TB [with a body mass index (BMI) of < 18.5 kg/m2] receive 0.6 L of vegetable oil and 6.0 kg of a soy-wheat blend per month throughout their TB treatment. METHODS: We analysed secondary non-governmental organisation data collected between January and November 2022 in the Atsimo-Andrefana region, Southern Madagascar, including information on an individual's medical conditions (e.g., type of TB, treatment outcomes) and nutritional status measured prior to, during, and after completion of treatment (e.g., height, weight, mid-upper arm circumference). We conducted descriptive analyses of patient baseline characteristics and outcomes to assess the impact of the provided nutritional support on the BMI of people with TB. RESULTS: A total of 1310 people with TB were included in the study [9.9% (130) children under the age of 5, 32.1% (420) children between 5 and 18 years, 58.0% (760) adults]. 55.4% of children under 5, 28.1% of children between ages 5 and 18, and 81.3% of adults were undernourished at treatment initiation. 42.3% (55/130) of children under 5 experienced severe acute malnutrition at treatment uptake. While the average BMI of adults with TB receiving food support increased over time, from 17.1 kg/m2 (interquartile range: 15.8-18.3, range: 10.3-22.5) to 17.9 kg/m2 (interquartile range: 16.6-19.1, range: 11.9-24.1), most adults remained undernourished even after completing TB treatment. CONCLUSIONS: The current TB nutritional support programme falls short of sufficiently increasing the BMI of people with TB to overcome malnutrition. There is an urgent need to revise the nutritional support available for people with TB, particularly for children under 5.

What predicts health facility delivery among women? analysis from the 2021 Madagascar Demographic and Health Survey.

BACKGROUND: One of the pivotal determinants of maternal and neonatal health outcomes hinges on the choice of place of delivery. However, the decision to give birth within the confines of a health facility is shaped by a complex interplay of sociodemographic, economic, cultural, and healthcare system-related factors. This study examined the predictors of health facility delivery among women in Madagascar. METHODS: We used data from the 2021 Madagascar Demographic and Health Survey. A total of 9,315 women who had a health facility delivery or delivered elsewhere for the most recent live birth preceding the survey were considered in this analysis. Descriptive analysis, and multilevel regression were carried out to determine the prevalence and factors associated with health facility delivery. The results were presented as frequencies, percentages, crude odds ratios and adjusted odds ratios (aORs) with corresponding 95% confidence intervals (CIs), and a p-value < 0.05 was used to declare statistical significance. RESULTS: The prevalence of health facility delivery was 41.2% [95% CI: 38.9-43.5%]. In the multilevel analysis, women aged 45-49 [aOR = 2.14, 95% CI = 1.34-3.43], those with secondary/higher education [aOR = 1.62, 95% CI = 1.30-2.01], widowed [aOR = 2.25, 95% CI = 1.43-3.58], and those exposed to mass media [aOR = 1.18, 95% CI = 1.00-1.39] had higher odds of delivering in health facilities compared to those aged 15-49, those with no formal education, women who had never been in union and not exposed to mass media respectively. Women with at least an antenatal care visit [aOR = 6.95, 95% CI = 4.95-9.77], those in the richest wealth index [aOR = 2.74, 95% CI = 1.99-3.77], and women who considered distance to health facility as not a big problem [aOR = 1.28, 95% CI = 1.09-1.50] were more likely to deliver in health facilities compared to those who had no antenatal care visit. Women who lived in communities with high literacy levels [aOR = 1.54, 95% CI = 1.15-2.08], and women who lived in communities with high socioeconomic status [aOR = 1.72, 95% CI = 1.28-2.31] had increased odds of health facility delivery compared to those with low literacy levels and in communities with low socioeconomic status respectively. CONCLUSION: The prevalence of health facility delivery among women in Madagascar is low in this study. The findings of this study call on stakeholders and the government to strengthen the healthcare system of Madagascar using the framework for universal health coverage. There is also the need to implement programmes and interventions geared towards increasing health facility delivery among adolescent girls and young women, women with no formal education, and those not exposed to media. Also, consideration should be made to provide free maternal health care and a health insurance scheme that can be accessed by women in the poorest wealth index. Health facilities should be provided at places where women have challenges with distance to other health facilities. Education on the importance of antenatal care visits should also be encouraged, especially among women with low literacy levels and in communities with low socioeconomic status.