Newly Identified Mycobacterium africanum Lineage 10, Central Africa.

Analysis of genome sequencing data from >100,000 genomes of Mycobacterium tuberculosis complex using TB-Annotator software revealed a previously unknown lineage, proposed name L10, in central Africa. Phylogenetic reconstruction suggests L10 could represent a missing link in the evolutionary and geographic migration histories of M. africanum.

An overview of artemisinin-resistant malaria and associated Pfk13 gene mutations in Central Africa.

Malaria caused by Plasmodium falciparum is one of the deadliest and most common tropical infectious diseases. However, the emergence of artemisinin drug resistance associated with the parasite's Pfk13 gene, threatens the public health of individual countries as well as current efforts to reduce malaria burdens globally. It is of concern that artemisinin-resistant parasites may be selected or have already emerged in Africa. This narrative review aims to evaluate the published evidence concerning validated, candidate, and novel Pfk13 polymorphisms in ten Central African countries. Results show that four validated non-synonymous polymorphisms (M476I, R539T, P553L, and P574L), directly associated with a delayed therapy response, have been reported in the region. Also, two Pfk13 polymorphisms associated to artemisinin resistance but not validated (C469F and P527H) have been reported. Furthermore, several non-validated mutations have been observed in Central Africa, and one allele A578S, is commonly found in different countries, although additional molecular and biochemical studies are needed to investigate whether those mutations alter artemisinin effects. This information is discussed in the context of biochemical and genetic aspects of Pfk13, and related to the regional malaria epidemiology of Central African countries.

Monkeypox Virus Infections in Humans.

Human monkeypox is a viral zoonosis endemic to West and Central Africa that has recently generated increased interest and concern on a global scale as an emerging infectious disease threat in the midst of the slowly relenting COVID-2019 disease pandemic. The hallmark of infection is the development of a flu-like prodrome followed by the appearance of a smallpox-like exanthem. Precipitous person-to-person transmission of the virus among residents of 100 countries where it is nonendemic has motivated the immediate and widespread implementation of public health countermeasures. In this review, we discuss the origins and virology of monkeypox virus, its link with smallpox eradication, its record of causing outbreaks of human disease in regions where it is endemic in wildlife, its association with outbreaks in areas where it is nonendemic, the clinical manifestations of disease, laboratory diagnostic methods, case management, public health interventions, and future directions.

Epidemiological Evidence of Nosocomial and Zoonotic Transmission of Human T-Cell Leukemia Virus-1 in a Large Survey in a Rural Population of Central Africa.

BACKGROUND: Central Africa is one of the largest areas of high endemicity for human T-cell leukemia virus-1 (HTLV-1). However, no preventive measures are yet implemented to reduce its transmission, which can be sexual, from mother-to-child, or through contaminated blood products. Rare zoonotic transmissions from nonhuman primates (NHPs) have also been reported in this region. Here we investigated the HTLV-1 prevalence and associated risk factors in a rural population in Cameroon. METHODS: From 2019 to 2021, we performed a cross-sectional survey in the eastern region of Cameroon. HTLV-1 infection was first screened by ELISA, then tested by western blot and envelope gene targeted polymerase chain reaction. Risk factors associated with HTLV-1 infection were identified by logistic regression in univariable and multivariable analyses. RESULTS: Among 3400 participants, HTLV-1 prevalence was 1.1% (95% confidence interval [CI], .7-1.5). Factors independently associated with HTLV-1 infection were Pygmy ethnicity (adjusted odd ratio [aOR], 2.9; 95% CI, 1.3-6.2), history of surgery (aOR, 6.3; 95% CI, 2.2-17.8), and NHP bite (aOR, 6.6; 95% CI, 2.2-19.8). CONCLUSIONS: These results suggest both iatrogenic and zoonotic transmission of HTLV-1 in Cameroon. Further studies are needed to assess the risk of nosocomial transmission of HTLV-1, to guide public health authorities in implementing preventive measures to control HTLV-1 transmission.

Mpox virus Clade IIb detection in the air.

Mpox is a viral zoonotic disease endemic in Central and West Africa that is caused by the Mpox virus, which belongs to the Orthopoxvirus genus and Poxviridae family. The clinical manifestations of mpox infection are milder than those of smallpox, and the incubation time of mpox varies from 5 to 21 days. Since May 2022, the mpox outbreak (formerly known as monkeypox) has suddenly and unexpectedly spread in non-endemic countries, suggesting that there may have been some undetected transmissions. Based on molecular analysis, there are two major genetic clades that represent the mpox virus: Clade I (formerly the Congo Basin clade OR the Central African clade) and Clade II (formerly the West African clade). It is believed that people who are asymptomatic or paucisymptomatic may spread the mpox virus. Infectious viruses cannot be distinguished by PCR testing; therefore, virus culture should be carried out. Recent evidence regarding the detection of the mpox virus (Clade IIb) in air samples collected from the patient's environment during the 2022 mpox outbreak was reviewed. Further studies are needed to evaluate the extent to which the presence of mpox virus DNA in the air could affect immunocompromised patients in healthcare facilities, and further epidemiological studies are crucial, especially in Africa.

National Monkeypox Surveillance, Central African Republic, 2001-2021.

We analyzed monkeypox disease surveillance in Central African Republic (CAR) during 2001-2021. Surveillance data show 95 suspected outbreaks, 40 of which were confirmed as monkeypox, comprising 99 confirmed and 61 suspected monkeypox cases. After 2018, CAR's annual rate of confirmed outbreaks increased, and 65% of outbreaks occurred in 2 forested regions bordering the Democratic Republic of the Congo. The median patient age for confirmed cases was 15.5 years. The overall case-fatality ratio was 7.5% (12/160) for confirmed and suspected cases, 9.6% (8/83) for children <16 years of age. Decreasing cross-protective immunity from smallpox vaccination and recent ecologic alterations likely contribute to increased monkeypox outbreaks in Central Africa. High fatality rates associated with monkeypox virus clade I also are a local and international concern. Ongoing investigations of zoonotic sources and environmental changes that increase human exposure could inform practices to prevent monkeypox expansion into local communities and beyond endemic areas.

Prevalence of human leukocyte antigen HLA-B*57:01 in individuals with HIV in West and Central Africa.

BACKGROUND: The presence of the human leukocyte antigen HLA-B*57:01 is associated with the development of a hypersensitivity reaction to abacavir (ABC). Limited data exist on HLA-B*57:01 prevalence in individuals with HIV-1 in Africa. This study aimed to estimate HLA-B*57:01 prevalence in individuals with HIV-1 in West and Central Africa. METHODS: A cross-sectional study was conducted in four countries in West and central Africa (Burkina-Faso, Côte d'Ivoire, Gabon, and Togo) from January 2016 to February 2020 to determine the status of HLA-B*57:01 in adults with HIV-1. The presence of HLA-B*57:01 was determined by using Single Specific Primer-Polymerase Chain Reaction (SSP-PCR) in blood samples. Prevalence rates were stratified based on country. RESULTS: A total of 4016 (69.8% women) individuals with HIV were enrolled. Their median age was 45, and the interquartile range was 38-52. We included 500 (12.4%) patients in Burkina-Faso, 1453 (36.2%) in Côte d'Ivoire, 951 (23.7%) in Gabon, and 1112 (27.7%) in Togo. The overall HLA-B*57:01 prevalence was 0.1% [95% CI: 0.0-0.2%]. The prevalence of HLA-B*57:01 was similar according to the four countries. Only one case was reported in each country except Togo, with no cases. CONCLUSIONS: HLA-B*57:01 prevalence is low in individuals with HIV in West and central Africa, and there is no difference among countries. This study does not confirm the utility of HLA-B*57:01 allele testing for abacavir use in this region.

Effectiveness of seasonal malaria chemoprevention at scale in west and central Africa: an observational study.

BACKGROUND: Seasonal malaria chemoprevention (SMC) aims to prevent malaria in children during the high malaria transmission season. The Achieving Catalytic Expansion of SMC in the Sahel (ACCESS-SMC) project sought to remove barriers to the scale-up of SMC in seven countries in 2015 and 2016. We evaluated the project, including coverage, effectiveness of the intervention, safety, feasibility, drug resistance, and cost-effectiveness. METHODS: For this observational study, we collected data on the delivery, effectiveness, safety, influence on drug resistance, costs of delivery, impact on malaria incidence and mortality, and cost-effectiveness of SMC, during its administration for 4 months each year (2015 and 2016) to children younger than 5 years, in Burkina Faso, Chad, The Gambia, Guinea, Mali, Niger, and Nigeria. SMC was administered monthly by community health workers who visited door-to-door. Drug administration was monitored via tally sheets and via household cluster-sample coverage surveys. Pharmacovigilance was based on targeted spontaneous reporting and monitoring systems were strengthened. Molecular markers of resistance to sulfadoxine-pyrimethamine and amodiaquine in the general population before and 2 years after SMC introduction was assessed from community surveys. Effectiveness of monthly SMC treatments was measured in case-control studies that compared receipt of SMC between patients with confirmed malaria and neighbourhood-matched community controls eligible to receive SMC. Impact on incidence and mortality was assessed from confirmed outpatient cases, hospital admissions, and deaths associated with malaria, as reported in national health management information systems in Burkina Faso and The Gambia, and from data from selected outpatient facilities (all countries). Provider costs of SMC were estimated from financial costs, costs of health-care staff time, and volunteer opportunity costs, and cost-effectiveness ratios were calculated as the total cost of SMC in each country divided by the predicted number of cases averted. FINDINGS: 12 467 933 monthly SMC treatments were administered in 2015 to a target population of 3 650 455 children, and 25 117 480 were administered in 2016 to a target population of 7 551 491. In 2015, among eligible children, mean coverage per month was 76·4% (95% CI 74·0-78·8), and 54·5% children (95% CI 50·4-58·7) received all four treatments. Similar coverage was achieved in 2016 (74·8% [72·2-77·3] treated per month and 53·0% [48·5-57·4] treated four times). In 779 individual case safety reports over 2015-16, 36 serious adverse drug reactions were reported (one child with rash, two with fever, 31 with gastrointestinal disorders, one with extrapyramidal syndrome, and one with Quincke's oedema). No cases of severe skin reactions (Stevens-Johnson or Lyell syndrome) were reported. SMC treatment was associated with a protective effectiveness of 88·2% (95% CI 78·7-93·4) over 28 days in case-control studies (2185 cases of confirmed malaria and 4370 controls). In Burkina Faso and The Gambia, implementation of SMC was associated with reductions in the number of malaria deaths in hospital during the high transmission period, of 42·4% (95% CI 5·9 to 64·7) in Burkina Faso and 56·6% (28·9 to 73·5) in The Gambia. Over 2015-16, the estimated reduction in confirmed malaria cases at outpatient clinics during the high transmission period in the seven countries ranged from 25·5% (95% CI 6·1 to 40·9) in Nigeria to 55·2% (42·0 to 65·3) in The Gambia. Molecular markers of resistance occurred at low frequencies. In individuals aged 10-30 years without SMC, the combined mutations associated with resistance to amodiaquine (pfcrt CVIET haplotype and pfmdr1 mutations [86Tyr and 184Tyr]) had a prevalence of 0·7% (95% CI 0·4-1·2) in 2016 and 0·4% (0·1-0·8) in 2018 (prevalence ratio 0·5 [95% CI 0·2-1·2]), and the quintuple mutation associated with resistance to sulfadoxine-pyrimethamine (triple mutation in pfdhfr and pfdhps mutations [437Gly and 540Glu]) had a prevalence of 0·2% (0·1-0·5) in 2016 and 1·0% (0·6-1·6) in 2018 (prevalence ratio 4·8 [1·7-13·7]). The weighted average economic cost of administering four monthly SMC treatments was US$3·63 per child. INTERPRETATION: SMC at scale was effective in preventing morbidity and mortality from malaria. Serious adverse reactions were rarely reported. Coverage varied, with some areas consistently achieving high levels via door-to-door campaigns. Markers of resistance to sulfadoxine-pyrimethamine and amodiaquine remained uncommon, but with some selection for resistance to sulfadoxine-pyrimethamine, and the situation needs to be carefully monitored. These findings should support efforts to ensure high levels of SMC coverage in west and central Africa. FUNDING: Unitaid.

Distinct rates and patterns of spread of the major HIV-1 subtypes in Central and East Africa.

Since the ignition of the HIV-1 group M pandemic in the beginning of the 20th century, group M lineages have spread heterogeneously throughout the world. Subtype C spread rapidly through sub-Saharan Africa and is currently the dominant HIV lineage worldwide. Yet the epidemiological and evolutionary circumstances that contributed to its epidemiological expansion remain poorly understood. Here, we analyse 346 novel pol sequences from the DRC to compare the evolutionary dynamics of the main HIV-1 lineages, subtypes A1, C and D. Our results place the origins of subtype C in the 1950s in Mbuji-Mayi, the mining city of southern DRC, while subtypes A1 and D emerged in the capital city of Kinshasa, and subtypes H and J in the less accessible port city of Matadi. Following a 15-year period of local transmission in southern DRC, we find that subtype C spread at least three-fold faster than other subtypes circulating in Central and East Africa. In conclusion, our results shed light on the origins of HIV-1 main lineages and suggest that socio-historical rather than evolutionary factors may have determined the epidemiological fate of subtype C in sub-Saharan Africa.

Unrecognized introduction of SARS-CoV-2 variants of concern to Central Africa: Import and local transmission of B.1.1.7 in Gabon in the very early stage of the variant spread to the African continent.

The rapid spread of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) variant of concern with higher infectivity has already resulted in the enormous increase in infection cases worldwide. We report an unrecognized introduction of the variant B.1.1.7 in Gabon in December 2020, which was the initial phase of the variant introduction to Africa. The B.1.1.7 variant was also detected in a hospitalized patient in January 2021, indicating a rapid spread of the variant in Gabon since its first detection. Phylogenetic analysis revealed that the detected B.1.1.7 variants originated from the distinct regions, strongly suggesting that the B.1.1.7 variant had been repeatedly introduced to Gabon since December 2020. These results provide insights on the unrecognized risks of infections with variants of concern, and show the necessity to conduct continuous genomic monitoring for immediate alert and control of novel SARS-CoV-2 variant infections.

Introduction and Dispersal of Sindbis Virus from Central Africa to Europe.

Bird-hosted viruses have the potential to be transported over large areas of the world and to be transmitted in distant geographical regions. Sindbis virus (SINV) is a mosquito-borne alphavirus that is locally amplified in a bird-mosquito enzootic cycle and distributed all over the Old World and Australia/Oceania. Sindbis virus genotype I (SINV-I) is the cause of disease outbreaks in humans in South Africa as well as in northern Europe. To trace the evolutionary history and potential strain-disease association of SINV-I, we sequenced 36 complete genomes isolated from field material in Europe, as well as in Africa and the Middle East, collected over 58 years. These were analyzed together with 30 additional published whole SINV-I genomes using Bayesian analysis. Our results suggested that SINV-I was introduced only once to northern Europe from central Africa, in the 1920s. After its first introduction to Sweden, it spread east and southward on two separate occasions in the 1960s and 1970s. Another introduction from central Africa to southern/central Europe seems to have occurred, and where these two introductions meet, one recombination event was detected in central Europe. In addition, another recombinant strain was found in central Africa, where the most divergent SINV-I strains also originated.IMPORTANCE This study shows that only a single introduction of SINV into a new geographical area is required for spread and establishment, provided that the requisite vector(s) and reservoir(s) of epizootological and epidemiological importance are present. Furthermore, we present the first report of recombination between two strains of SINV in nature. Our study increases the knowledge on new introductions and dispersal of arboviruses in general and of SINV in particular.

Ongoing evolution of hepatitis B virus during viremia in patients with febrile in Central Africa.

Hepatitis B virus (HBV) infection remains to be a major public health issue worldwide, although there is currently a safe vaccine and effective antiviral treatments. In surveillance of infectious diseases in Gabon, HBV viremia was detected in patients with febrile. Whole-genome sequencing was conducted to characterize the HBV strains currently circulating in Gabon and to investigate HBV genome diversity during viremia. Phylogenetic analysis revealed the existence of former subgenotype A5, which exhibits a particular pattern of distribution from several West and Central African countries to Haiti. Furthermore, sequencing analysis identified two similar HBV strains mixed in one sample, and a very rare 1-base pair insertion in the viral precore region. This insertion caused a frameshift mutation, indicating the production of an aberrant fusion protein of the HBV x and e antigens. Our data showed that the detected HBV strain was possibly in an "evolving" state during viremia, a phase of active replication.

An evolutionary insight into emerging Ebolavirus strains isolated in Africa.

On July 19, 2019, the World Health Organization declared the current Ebolavirus (EBOV) outbreak in Congo Democratic Republic (COD) a public health emergency of international concern. To address the potential threat of EBOV evolution outpacing antibody treatment and vaccine efforts, a detailed evolutionary analysis of EBOV strains circulating in different African countries was performed. Genome composition of EBOV strains was studied using multivariate statistical analysis. To investigate the patterns of evolution of EBOV strains, a Bayesian Markov Chain Monte Carlo approach was used. Two different genetic lineages, with a distinct genome composition gave rise to the recent EBOV outbreaks in central and western Africa. Strains isolated in COD in 2018 fall into two different genetic clusters, according to their geographical location of isolation. Different amino acid substitutions among strains from these two clusters have been found, particularly in NP, GP, and L proteins. Significant differences in codon and amino acid usage among clusters were found. Strains isolated in COD in 2018 belong to two distinct genetic clusters, with distinct codon and amino acid usage. Geographical diversity plays an important role in shaping the molecular evolution of EBOV populations.

Predictors of Burnout and Depression in Surgeons Practicing in East, Central, and Southern Africa.

BACKGROUND: Surgeons are at risk of burnout and depression, which can lead to medical errors, inefficiency, exhaustion, conflicts, and suicide. Significant challenges exist in sub-Saharan Africa that may increase the prevalence of burnout and depression, but no formal evaluation has identified stressors specific to this environment. METHODS: A survey was distributed to all members of the College of Surgeons of East, Central, and Southern Africa (COSECSA). Burnout, depression, and stressors were assessed with validated measures: Maslach Burnout Inventory for Medical Personnel, Patient Health Questionnaire (PHQ) 9, and Holmes-Rahe Life Stress Inventory. RESULTS: There were 131 participants (98 African and 33 non-African surgeons). The incidence of moderate to severe depression was 48% (n = 63), and the incidence of burnout was as high as 38% (n = 48). There were no significant differences between African and non-African surgeons in marital status, number of children, partners in practice, or distribution of time. More African surgeons experienced birth of a child (18% versus 3%, P = 0.04) but had less workplace conflict (7.1% versus 10.7%, P = 0.045) than non-African surgeons. African surgeons more consistently felt they were positively influencing others (P = 0.008), enjoyed working with patients (P = 0.009), and were more satisfied (P = 0.04). For all surgeons, predictors of increased PHQ-9 depression were serious professional conflict (P = 0.02), difficulty accessing childcare (P = 0.04), and racial discrimination (P = 0.003). In the Maslach model, predictors of burnout were difficulty accessing childcare (P = 0.05) and denial of promotion based on gender (P = 0.006). CONCLUSIONS: Burnout and depression in surgeons practicing in East, Central, and Southern Africa are substantial. Despite significant challenges, African surgeons tended to have a more positive outlook on their work. Improvements can be made to reduce burnout and depression by focusing on work conditions, equality of promotion opportunities, workplace conflict management, childcare support, and increasing the numbers of surgeons in practice.

Delivery mode for prolonged, obstructed labour resulting in obstetric fistula: a retrospective review of 4396 women in East and Central Africa.

OBJECTIVE: To evaluate the mode of delivery and stillbirth rates over time among women with obstetric fistula. DESIGN: Retrospective record review. SETTING: Tanzania, Uganda, Kenya, Malawi, Rwanda, Somalia, South Sudan, Zambia and Ethiopia. POPULATION: A total of 4396 women presenting with obstetric fistulas for repair who delivered previously in facilities between 1990 and 2014. METHODS: Retrospective review of trends and associations between mode of delivery and stillbirth, focusing on caesarean section (CS), assisted vaginal deliveries and spontaneous vaginal deliveries. MAIN OUTCOME MEASURES: Mode of delivery, stillbirth. RESULTS: Out of 4396 women with fistula, 3695 (84.1%) delivered a stillborn baby. Among mothers with fistula giving birth to a stillborn baby, the CS rate (overall 54.8%, 2027/3695) rose from 45% (162/361) in 1990-94 to 64% (331/514) in 2010-14. This increase occurred at the expense of assisted vaginal delivery (overall 18.3%, 676/3695), which declined from 32% (115/361) to 6% (31/514). CONCLUSIONS: In Eastern and Central Africa, CS is increasingly performed on women with obstructed labour whose babies have already died in utero. Contrary to international recommendations, alternatives such as vacuum extraction, forceps and destructive delivery are decreasingly used. Unless uterine rupture is suspected, CS should be avoided in obstructed labour with intrauterine fetal death to avoid complications related to CS scars in subsequent pregnancies. Increasingly, women with obstetric fistula add a history of unnecessary CS to their already grim experiences of prolonged, obstructed labour and stillbirth. TWEETABLE ABSTRACT: Caesarean section is increasingly performed in African women with stillbirth treated for obstetric fistula.

Serologic Prevalence of Ebola Virus in Equatorial Africa.

We conducted a serologic survey of 2,430 serum samples collected during 1997-2012 for various studies to determine the prevalence of the hemorrhagic fever virus Ebola virus (EBOV) in equatorial Africa. We screened serum samples for neutralizing antibodies by using a pseudotype microneutralization assay and a newly developed luciferase immunoprecipitation system assay. Specimens seroreactive for EBOV were confirmed by using an ELISA. Our results suggest a serologic prevalence of 2%-3.5% in the Republic of the Congo and the Democratic Republic of the Congo, which have reported outbreaks of infection with EBOV. In addition we detected a seroprevalence of 1.3% in southern Cameroon, which indicated a low risk for exposure in this region.

Neuropsychiatric symptoms among older adults living in two countries in Central Africa (EPIDEMCA study).

OBJECTIVES: Our study aimed at estimating the prevalence of neuropsychiatric symptoms and investigating associated factors among older adults living in two countries in Central Africa (Central African Republic [CAR] and Republic of Congo [ROC]). METHODS: The EPIDEMCA multicentre population-based study was carried out in rural and urban areas of CAR and ROC between 2011 and 2012 among people aged 65 and over. After cognitive screening using the Community Screening Interview for Dementia, participants with low performances underwent neurological examination including the brief version of the Neuropsychiatric Inventory Questionnaire (NPI-Q). Multivariate logistic regression analyses were performed to identify factors independently associated with neuropsychiatric symptoms in this population. RESULTS: NPI-Q data were available for 532 participants. Overall, 333 elderly people (63.7%) reported at least one neuropsychiatric symptom. The prevalence of neuropsychiatric symptoms was 89.9% (95% CI, 84.6-95.1) in participants with dementia, 73.4% (95% CI, 65.1-81.7) in participants with mild cognitive impairment (MCI), and 48.7% (95% CI, 42.9-54.6) in participants with no MCI nor dementia after neurological examination (P < 0.0001). The most common symptoms were depression, anxiety, and irritability. Participants living in Gamboma, with normal hearing and with friends in the community, were less likely to present neuropsychiatric symptoms. Physical disability, difficulties in eating, female sex, and dementia were significantly associated with neuropsychiatric symptoms. CONCLUSION: Neuropsychiatric symptoms are common among older people with neurocognitive disorders in CAR and ROC. Our results confirm those from previous studies in Nigeria and Tanzania. Nevertheless, knowledge of these symptoms remains limited in sub-Saharan Africa, hampering their appropriate management.

Population genetics of IFITM3 in Portugal and Central Africa reveals a potential modifier of influenza severity.

Influenza epidemics are a serious global public health and economic problem. The IFITM3 allele (rs12252-C) was suggested as a population-based genetic risk factor for severe influenza virus infection by A(H1N1)pdm09. We analyzed the population genetics of IFITM3 variants in the Portuguese general population (n = 200) and Central Africans (largely Angolan) (n = 148) as well as its association to influenza severity in Portuguese patients (n = 41). Seven SNPs, within the 352 bp IFITM3 amplicon around rs12252, were identified. SNP distributions in the Portuguese appeared at an intermediate level between the Africans and other Europeans. According to HapMap, rs34481144 belongs to the same linkage disequilibrium (LD) block as rs12252 and is in strong LD with rs6421983. A negative association with severe relative to mild disease was observed for allele rs34481144-A, indicating a protective effect under the dominant model. Moreover, haplotype Hap4 with rs34481144-A, not including rs12252-C, was significantly associated to mild influenza. Conversely, although with borderline significance, haplotype Hap1 with rs34481144-G, not including rs12252-C, was associated to severe disease. Moreover, in comparison to the general Portuguese population, statistical significant differences in the frequencies of the protective allele rs34481144-A in the severe disease group, the deleterious Hap1 in the mild disease group, and the protective Hap4 in the severe disease group were observed. The population attributable risk (PAR) for the targeted rs34481144 allele or genotype was of 55.91 and 64.44% in the general population and the mildly infected individuals, respectively. Implication of these variants in disease phenotype needs further validation, namely through functional analysis as is discussed.

Prevalence of toxoplasmosis and its association with dementia in older adults in Central Africa: a result from the EPIDEMCA programme.

OBJECTIVE: We aimed at estimating the seroprevalence of Toxoplasma gondii (T. gondii) infection in older adults living in Central Africa and investigating its association with dementia using data from the Epidemiology of Dementia in Central Africa (EPIDEMCA) programme. METHODS: A cross-sectional multicentre population-based study was carried out among participants aged 73 (±7) years on average, living in rural and urban areas of the Central African Republic and the Republic of Congo between November 2011 and December 2012. Blood samples were collected from each consenting participant. The detection of anti-T. gondii immunoglobulin G antibodies was performed in 2014 in France using a commercially available ELISA kit. Participants were interviewed using a standardised questionnaire including sociodemographic characteristics. DSM-IV criteria were required for a diagnosis of dementia. Multivariate binary logistic regression models were used to assess the association between toxoplasmosis infection and dementia. RESULTS: Among 1662 participants, the seroprevalence of toxoplasmosis was 63.0% (95% confidence interval (CI): 60.7-65.3) overall, 66.6% (95%CI: 63.4-69.8) in Central African Republic and 59.4% (95%CI: 56.1-62.7) in the Republic of Congo. In multivariate analyses, toxoplasmosis status was significantly associated with increasing age (P = 0.006), Republic of Congo (P = 0.002), urban area (P = 0.001) and previous occupation (P = 0.002). No associations between dementia and toxoplasmosis status or anti-T. gondii IgG titres were found. CONCLUSION: Toxoplasma gondii infection was not associated with dementia among older adults in Central Africa. Our findings are consistent with previous studies and add to the knowledge on the relationship between T. gondii infection and neurological disorders.