Seroprevalence of anti-SARS-CoV-2 IgG antibodies in Juba, South Sudan: a population-based study

AbstractBackgroundRelatively few COVID-19 cases and deaths have been reported through much of sub-Saharan Africa, including South Sudan, although the extent of SARS-CoV-2 spread remains unclear due to weak surveillance systems and few population-representative serosurveys.MethodsWe conducted a representative household-based cross-sectional serosurvey in Juba, South Sudan. We quantified IgG antibody responses to SARS-CoV-2 spike protein receptor-binding domain and estimated seroprevalence using a Bayesian regression model accounting for test performance.ResultsWe recruited 2,214 participants from August 10 to September 11, 2020 and 22.3% had anti-SARS-CoV-2 IgG titers above levels in pre-pandemic samples. After accounting for waning antibody levels, age, and sex, we estimated that 38.5% (32.1 - 46.8) of the population had been infected with SARS-CoV-2. For each RT-PCR confirmed COVID-19 case, 104 (87-126) infections were unreported. Background antibody reactivity was higher in pre-pandemic samples from Juba compared to Boston, where the serological test was validated. The estimated proportion of the population infected ranged from 30.1% to 60.6% depending on assumptions about test performance and prevalence of clinically severe infections.ConclusionsSARS-CoV-2 has spread extensively within Juba. Validation of serological tests in sub-Saharan African populations is critical to improve our ability to use serosurveillance to understand and mitigate transmission.

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SARS-CoV-2 seroassay optimization and performance in a population with high background reactivity in Mali

10.1101/2021.03.08.21252784 ◽

2021 ◽

Author(s):

Issaka Sagara ◽

John Woodford ◽

Alassane Dicko ◽

Amatigue Zeguime ◽

M’Bouye Doucoure ◽

...

Keyword(s):

Test Performance ◽

Neutralization Assay ◽

Cross Reactivity ◽

Control Measures ◽

Sub Saharan Africa ◽

Spike Protein ◽

Roc Curve Analysis ◽

Serological Tests ◽

High Background ◽

Sub Saharan

ABSTRACTSerological tests are an indispensable tool to understand the epidemiology of the SARS-CoV-2 pandemic, particularly in areas where molecular diagnostics are limited. Poor assay performance may hinder the utility of these tests, including high rates of false-positivity previously reported in sub-Saharan Africa. From 312 Malian samples collected prior to 2020, we measured antibodies to the commonly tested SARS-CoV-2 antigens and four other betacoronaviruses by ELISA, and assessed functional cross-reactivity in a subset by SARS-CoV-2 pseudovirus neutralization assay. We then evaluated the performance of an ELISA developed in the US, using two-antigen SARS-CoV-2 spike protein and receptor-binding domain. To optimize test performance, we compared single and two-antigen approaches using existing assay cutoffs and population-specific cutoffs for Malian control samples (positive and negative). Background reactivity to SARS-CoV-2 antigens was common in pre-pandemic samples compared to US controls (43.4% (135/311) for spike protein, 22.8% (71/312) for RBD, and 33.9% (79/233) for nucleocapsid protein). SARS-CoV-2 reactivity correlated weakly with other betacoronavirus reactivity, varied between Malian communities, and increased with age. No pre-pandemic samples demonstrated functional activity. Regardless of the cutoffs applied, specificity improved using a two-antigen approach. Test performance was optimal using a two-antigen assay with population-specific cutoffs derived from ROC curve analysis [Sensitivity: 73.9% (51.6-89.8), Specificity: 99.4% (97.7-99.9)]. In the setting of high background reactivity, such as sub-Saharan Africa, SARS-CoV-2 serological assays need careful qualification is to characterize the epidemiology of disease, prevent unnecessary harm, and allocate resources for targeted control measures.

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Latent class evaluation of the performance of serological tests for exposure to Brucella spp. in cattle, sheep, and goats in Tanzania

PLoS Neglected Tropical Diseases ◽

10.1371/journal.pntd.0009630 ◽

2021 ◽

Vol 15 (8) ◽

pp. e0009630

Author(s):

Rebecca F. Bodenham ◽

Stella Mazeri ◽

Sarah Cleaveland ◽

John A. Crump ◽

Folorunso O. Fasina ◽

...

Keyword(s):

Test Performance ◽

Prevention And Control ◽

Latent Class ◽

Sub Saharan Africa ◽

Diagnostic Tools ◽

Serological Tests ◽

Sheep And Goats ◽

Parallel Testing ◽

Sub Saharan ◽

And Control

Background Brucellosis is a neglected zoonosis endemic in many countries, including regions of sub-Saharan Africa. Evaluated diagnostic tools for the detection of exposure to Brucella spp. are important for disease surveillance and guiding prevention and control activities. Methods and findings Bayesian latent class analysis was used to evaluate performance of the Rose Bengal plate test (RBT) and a competitive ELISA (cELISA) in detecting Brucella spp. exposure at the individual animal-level for cattle, sheep, and goats in Tanzania. Median posterior estimates of RBT sensitivity were: 0.779 (95% Bayesian credibility interval (BCI): 0.570–0.894), 0.893 (0.636–0.989), and 0.807 (0.575–0.966), and for cELISA were: 0.623 (0.443–0.790), 0.409 (0.241–0.644), and 0.561 (0.376–0.713), for cattle, sheep, and goats, respectively. Sensitivity BCIs were wide, with the widest for cELISA in sheep. RBT and cELISA median posterior estimates of specificity were high across species models: RBT ranged between 0.989 (0.980–0.998) and 0.995 (0.985–0.999), and cELISA between 0.984 (0.974–0.995) and 0.996 (0.988–1). Each species model generated seroprevalence estimates for two livestock subpopulations, pastoralist and non-pastoralist. Pastoralist seroprevalence estimates were: 0.063 (0.045–0.090), 0.033 (0.018–0.049), and 0.051 (0.034–0.076), for cattle, sheep, and goats, respectively. Non-pastoralist seroprevalence estimates were below 0.01 for all species models. Series and parallel diagnostic approaches were evaluated. Parallel outperformed a series approach. Median posterior estimates for parallel testing were ≥0.920 (0.760–0.986) for sensitivity and ≥0.973 (0.955–0.992) for specificity, for all species models. Conclusions Our findings indicate that Brucella spp. surveillance in Tanzania using RBT and cELISA in parallel at the animal-level would give high test performance. There is a need to evaluate strategies for implementing parallel testing at the herd- and flock-level. Our findings can assist in generating robust Brucella spp. exposure estimates for livestock in Tanzania and wider sub-Saharan Africa. The adoption of locally evaluated robust diagnostic tests in setting-specific surveillance is an important step towards brucellosis prevention and control.

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Cross-sectional study of IgG antibody levels to invasive nontyphoidal Salmonella LPS O-antigen with age in Uganda

Gates Open Research ◽

10.12688/gatesopenres.13034.1 ◽

2019 ◽

Vol 3 ◽

pp. 1501

Author(s):

Lisa Stockdale ◽

Angela Nalwoga ◽

Stephen Nash ◽

Sean Elias ◽

Gershim Asiki ◽

...

Keyword(s):

Old Age ◽

Cross Sectional Study ◽

Sub Saharan Africa ◽

Igg Antibody ◽

Cross Sectional ◽

O Antigen ◽

Cause Of Deaths ◽

Specific Igg ◽

Sub Saharan ◽

Antibody Levels

Invasive nontyphoidal Salmonella (iNTS) disease is a major cause of deaths among children and HIV-infected individuals in sub-Saharan Africa. Acquisition of IgG to iNTS lipopolysaccharide (LPS) O-antigen in Malawi in early childhood corresponds with a fall in cases of iNTS disease suggesting that vaccines able to induce such antibodies could confer protection. To better understand the acquisition of IgG to iNTS in other African settings, we performed a cross-sectional seroepidemiological study using sera from 1090 Ugandan individuals aged from infancy to old age. Sera were analysed for IgG to LPS O-antigen of S. Typhimurium and S. Enteritidis using an in-house ELISA. Below 18 months of age, most children lacked IgG to both serovars. Thereafter, specific IgG levels increased with age, peaking in adulthood, and did not wane noticeably in old age. There was no clear difference in antibody levels between the sexes and the few HIV-infected individuals in the study did not have obviously different levels from uninfected subjects. While IgG to iNTS is acquired at a younger age in Malawian compared with Ugandan children, it is not clear whether this is due to differences in the populations themselves, their exposure to iNTS, or variations between assays used. In conclusion, there is a need to develop a harmonised method and standards for measuring antibodies to iNTS across studies and to investigate acquisition of such antibodies with age across different sites in sub-Saharan Africa.

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Prevalence and Factors Associated with Malnutrition in Children Aged 6-59 Months in Jubek State, South Sudan.

10.21203/rs.3.rs-15585/v1 ◽

2020 ◽

Author(s):

Martin Adelino Iyya ◽

Ndeezi Grace ◽

Nabukeera Barungi Nicolette ◽

Hassan Chollong

Keyword(s):

Diarrheal Disease ◽

South Sudan ◽

Public Health Problem ◽

Sub Saharan Africa ◽

Acute Malnutrition ◽

Cross Sectional ◽

Factors Associated ◽

Hiv Test ◽

Sub Saharan ◽

Structured Questionnaire

Abstract Background: South Sudan is the world’s youngest nation which gained independence from Sudan on the 9th of July, 2011. Rates of acute malnutrition have been consistently higher in South Sudan than any other country in sub-Saharan Africa, more than twice the average reported for countries in Sub-Saharan Africa. This study sought to determine the prevalence and factors associated with malnutrition among children aged 6-59 months in Jubek State, South Sudan.Methods: This was a cross sectional analytical community based study to assess the prevalence and factors associated with malnutrition among children aged 6-59 months in Jubek State, South Sudan. Data was collected using a structured questionnaire from 396 children. Anthropometric measurements including weight, length/ height, mid upper arm circumference (MUAC) were taken and a blood sample by finger prick was removed for HIV test. The equipment which were used included: WHO recommended MUAC tape for 6months to 59 months old children, digital weighing scale (SECCA) and portable Stadiometers. Data were collected using a pretested semi- structured questionnaire. Results: The analysis of this study revealed that, 32.2%, 28.2% and 32.3% of children were stunted, wasted and underweight respectively. The main associated factors of stunting were age older than one year (p= 0.004), children from households who were renting their houses and children who defecate in open spaces with no latrine at their homes (p= 0.015). Underweight was associated with child’s age (p= 0.001), loss of appetite (p=<0.001), children who ate from own plate (p=0.001) and children who didn’t consume meat (p=0.007). Male genders (p=0.022), households with two or more children aged zero to five years (0.010) not consuming vitamin A rich vegetable (p=0.002), diarrheal disease within two weeks prior to interview (p=0.006) and those from households with water sources other than piped (<0.001) were also associated with wasting. Conclusion:The findings of this study indicate that malnutrition is still a serious public health problem among children below five years of age in Jubek state, South Sudan. Emergency intervention measures to address this critical levels of malnutrition are required.

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Adolescent Suicidality as Seen in Rural Northeastern Uganda

Crisis ◽

10.1027/0227-5910/a000059 ◽

2011 ◽

Vol 32 (1) ◽

pp. 43-51 ◽

Cited By ~ 17

Author(s):

Eugene Kinyanda ◽

Ruth Kizza ◽

Jonathan Levin ◽

Sheila Ndyanabangi ◽

Catherine Abbo

Keyword(s):

Low Socioeconomic Status ◽

Sub Saharan Africa ◽

Psychosocial Risk ◽

Psychiatric Nurses ◽

Health Concern ◽

Cross Sectional ◽

Childhood Experiences ◽

Low Socioeconomic ◽

Dsm Iv ◽

Sub Saharan

Background: Suicidal behavior in adolescence is a public health concern and has serious consequences for adolescents and their families. There is, however, a paucity of data on this subject from sub-Saharan Africa, hence the need for this study. Aims: A cross-sectional multistage survey to investigate adolescent suicidality among other things was undertaken in rural northeastern Uganda. Methods: A structured protocol administered by trained psychiatric nurses collected information on sociodemographics, mental disorders (DSM-IV criteria), and psychological and psychosocial risk factors for children aged 3–19 years (N = 1492). For the purposes of this paper, an analysis of a subsample of adolescents (aged 10–19 years; n = 897) was undertaken. Results: Lifetime suicidality in this study was 6.1% (95% CI, 4.6%–7.9%). Conclusions: Factors significantly associated with suicidality included mental disorder, the ecological factor district of residence, factors suggestive of low socioeconomic status, and disadvantaged childhood experiences.

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Crowdsourcing Covid-19 signals in sub-Saharan Africa: Leveraging digital contributor networks for participatory surveillance of Covid-19 symptoms and deaths (Preprint)

10.2196/preprints.26347 ◽

2020 ◽

Author(s):

Ngozi A Erondu ◽

Sagal A Ali ◽

Mohamed Ali ◽

Schadrac C Agbla

Keyword(s):

Public Health ◽

Sub Saharan Africa ◽

Specific Information ◽

Surveillance Systems ◽

Health Seeking ◽

African Countries ◽

Cross Sectional Survey ◽

Local Networks ◽

The World ◽

Sub Saharan

BACKGROUND In sub-Saharan Africa, underreporting of cases and deaths has been attributed to various factors including, weak disease surveillance, low health-seeking behaviour of flu like symptoms, and stigma of Covid-19. There is evidence that SARS-CoV-2 spread mimics transmission patterns of other countries across the world. Since the Covid-19 pandemic has changed the way research can be conducted and in light of restrictions on travel and risks to in-person data collection, innovative approaches to collecting data must be considered. Nearly 50% of Africa’s population is a unique mobile subscriber and it is one of the fastest growing smart-phone marketplaces in the world; hence, mobile phone platforms should be considered to monitor Covid-19 trends in the community. OBJECTIVE We demonstrate the use of digital contributor platforms to survey individuals about cases of flu-like symptoms and instances of unexplained deaths in Ethiopia, Kenya, Nigeria, Somalia, and Zimbabwe. METHODS Rapid cross-sectional survey of individuals with severe flu and pneumonia symptoms and unexplained deaths in Ethiopia, Kenya, Nigeria, Somalia and Zimbabwe RESULTS Using a non-health specific information platform, we found COVID-19 signals in five African countries, specifically: •Across countries, nearly half of the respondents (n=739) knew someone who had severe flu or pneumonia symptoms in recent months. •One in three respondents from Somalia and one in five from Zimbabwe respondents said they knew more than five people recently displaying flu and/or pneumonia symptoms. •In Somalia there were signals that a large number of people might be dying outside of health facilities, specifically in their homes or in IDP or refugee camps. CONCLUSIONS Existing digital contributor platforms with local networks are a non-traditional data source that can provide information from the community to supplement traditional government surveillance systems and academic surveys. We demonstrate that using these distributor networks to for community surveys can provide periodic information on rumours but could also be used to capture local sentiment to inform public health decision-making; for example, these insights could be useful to inform strategies to increase confidence in Covid19 vaccine. As Covid-19 continues to spread somewhat silently across sub-Saharan Africa, regional and national public health entities should consider expanding event-based surveillance sources to include these systems.

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Suicidal ideation and associated factors among school-going adolescents in rural Ghana

Current Psychology ◽

10.1007/s12144-021-01378-3 ◽

2021 ◽

Author(s):

Emmanuel Nii-Boye Quarshie ◽

Samuel Kofi Odame

Keyword(s):

Suicidal Ideation ◽

Associated Factors ◽

Attempted Suicide ◽

Sub Saharan Africa ◽

Rural Adolescents ◽

African Countries ◽

Cross Sectional Survey ◽

Cross Sectional ◽

Rural Ghana ◽

Sub Saharan

AbstractSuicidal ideation is a critical risk for attempted suicide and eventual suicide. Little is known about suicidal ideation among rural adolescents in most sub-Saharan African countries. We aimed to estimate the 12-month prevalence of suicidal ideation and to describe some of the common and gender-specific associated factors among in-school adolescents in rural Ghana. We conducted a cross-sectional survey involving a random sample of 1101 in-school adolescents aged 10–19 years in a rural district in Eastern Ghana. The Suicidal Behavior Questionnaire-Revised was used to assess suicidal ideation. Overall, 25.1% participants (95% CI = 22.5–27.7), representing 28.3% females (95% CI = 24.7–32.2) and 21.5% males (95% CI = 18.0–25.2) reported suicidal ideation during the previous 12 months. Females who experienced personal and interpersonal adversities mainly outside the family context were likely to report suicidal ideation, while suicidal ideation among males was associated with conflict with parents. Regardless of gender, adolescents who reported exposure to a friend’s attempted suicide were about two times more likely to report suicidal ideation. The prevalence of suicidal ideation among adolescents in rural Ghana compares with in-school estimates from other countries within sub-Saharan Africa, but also underscores the need for targeted and universal prevention programmes and intervention efforts to mitigate the potential transition from suicidal ideations to suicidal attempts and eventual deaths by suicide among rural adolescents.

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Maternal healthcare utilsation and complete childhood vaccination in sub-Saharan Africa: a cross-sectional study of 29 nationally representative surveys

BMJ Open ◽

10.1136/bmjopen-2020-045992 ◽

2021 ◽

Vol 11 (5) ◽

pp. e045992

Author(s):

Eugene Budu ◽

Bright Opoku Ahinkorah ◽

Richard Gyan Aboagye ◽

Ebenezer Kwesi Armah-Ansah ◽

Abdul-Aziz Seidu ◽

...

Keyword(s):

Healthcare Utilisation ◽

Cross Sectional Study ◽

Sub Saharan Africa ◽

Childhood Vaccination ◽

Outcome Variable ◽

Service Utilisation ◽

Sectional Study ◽

Maternal Healthcare ◽

Cross Sectional ◽

Sub Saharan

ObjectiveThe objective of the study was to examine the association between maternal healthcare utilisation and complete childhood vaccination in sub-Saharan Africa.DesignOur study was a cross-sectional study that used pooled data from 29 countries in sub-Saharan Africa.ParticipantsA total of 60 964 mothers of children aged 11–23 months were included in the study.Outcome variablesThe main outcome variable was complete childhood vaccination. The explanatory variables were number of antenatal care (ANC) visits, assistance during delivery and postnatal care (PNC).ResultsThe average prevalence of complete childhood vaccination was 85.6%, ranging from 67.0% in Ethiopia to 98.5% in Namibia. Our adjusted model, children whose mothers had a maximum of three ANC visits were 56% less likely to have complete vaccination, compared with those who had at least four ANC visits (adjusted OR (aOR)=0.44, 95% CI 0.42 to 0.46). Children whose mothers were assisted by traditional birth attendant/other (aOR=0.43, 95% CI 0.41 to 0.56) had lower odds of complete vaccination. The odds of complete vaccination were lower among children whose mothers did not attend PNC clinics (aOR=0.26, 95% CI 0.24 to 0.29) as against those whose mothers attended.ConclusionThe study found significant variations in complete childhood vaccination across countries in sub-Saharan Africa. Maternal healthcare utilisation (ANC visits, skilled birth delivery, PNC attendance) had significant association with complete childhood vaccination. These findings suggest that programmes, interventions and strategies aimed at improving vaccination should incorporate interventions that can enhance maternal healthcare utilisation. Such interventions can include education and sensitisation, reducing cost of maternal healthcare and encouraging male involvement in maternal healthcare service utilisation.

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Unravelling the Perspectives of Day and Night Traders in Selected Markets within a Sub-Saharan African City with a Malaria Knowledge, Attitude and Practice Survey

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph18073468 ◽

2021 ◽

Vol 18 (7) ◽

pp. 3468

Author(s):

Patience B. Tetteh-Quarcoo ◽

Nicholas T. K. D. Dayie ◽

Kevin Kofi Adutwum-Ofosu ◽

John Ahenkorah ◽

Emmanuel Afutu ◽

...

Keyword(s):

Cross Sectional Study ◽

Malaria Treatment ◽

Sub Saharan Africa ◽

African City ◽

Cross Sectional ◽

Attitudes And Practices ◽

Treatment Type ◽

Significant Difference ◽

High Knowledge ◽

Sub Saharan

Background: Malaria is still endemic in sub-Saharan Africa, with a high disease burden. Misconceptions about malaria contribute to poor attitudes and practices, further increasing the burden in endemic countries. Studies have examined the knowledge, attitudes, and practices (KAP) of malaria among different populations. However, there seems to be no available literature reporting on the perspectives of day and night market traders. To the best of our knowledge, this is the first report on malaria KAP with a focus on day and night market traders. Methods: A descriptive cross-sectional study involving day and night market traders in 10 selected markets within the Greater Accra Region of Ghana was carried out. Data were collected from consenting respondents using a structured questionnaire. Results: Of the 760 respondents (33.3% (n = 253) night and 66.7% (n = 507) day traders) interviewed, there was no significant difference between the day and night market traders in terms of malaria KAP. Although the market traders had an overall moderate knowledge (54.0% of the day traders and 56.5% of the night traders), misconceptions about malaria (especially that it could be caused by exposure to the sun) still existed among the traders. Moreover, the majority of the traders who demonstrated high knowledge (43.98%, n = 250) did not always take laboratory tests to confirm their suspicion, indicating poor attitude. Furthermore, the market traders’ choice of drug for malaria treatment (p = 0.001) and preferred malaria treatment type (orthodox or herbal) (p = 0.005) were significantly associated with their knowledge level. Conclusions: Despite the observation that no significant difference in KAP exists between day and night market traders, appropriate health education programs and interventions still need to be directed at misconceptions, poor attitudes, and poor practices revealed by this study. This will ultimately help in the prevention and control of malaria in Ghana, and globally.

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