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

BACKGROUND

Relatively 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.

METHODS

We 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.

RESULTS

We 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.

CONCLUSIONS

SARS-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.

Focused ultrasound to diagnose HIV-associated tuberculosis (FASH) in the extremely resource-limited setting of South Sudan: a cross-sectional study

OBJECTIVE

Our cross-sectional study aimed at evaluating the diagnostic performance of Focused Assessment with Sonography for HIV-associated tuberculosis (FASH) to detect extrapulmonary tuberculosis in extremely resource-limited settings, with visceral leishmaniasis as a differential diagnosis with overlapping sonographic feature.

DESIGN

Cross-sectional study.

SETTING

Voluntary Counselling and Testing Centre (VCT) of Yirol Hospital, South Sudan.

PARTICIPANTS

From May to November 2017, 252 HIV-positive patients out of 624 newly admitted to VCT Centre were registered for antiretroviral treatment. According to the number of trained doctors available to practise ultrasound (US) scan, a sample of 100 patients were screened using the FASH protocol.

INTERVENTIONS

Following a full clinical examination, each patient was scanned with a portable US scanner in six different positions for pleural, pericardial, ascitic effusion, abdominal lymphadenopathy and hepatic/splenic microabscesses, according to the FASH protocol. A k39 antigen test for visceral leishmaniasis was also performed on patients with lymphadenopathy and/or splenomegaly. All demographic, clinical and HIV data, as well as FASH results and therapy adjustments, were recorded following the examination.

RESULTS

The FASH protocol allowed the detection of pathological US findings suggestive of tuberculosis in 27 out of the 100 patients tested. Overall, FASH results supported tuberculosis treatment indication for 16 of 21 patients, with the treatment being based exclusively on FASH findings in half of them (8 patients). The group of FASH-positive patients had a significantly higher proportion of patients with CD4 count below 0.2 x10⁹/L (n=22, 81%) as compared with FASH-negative patients (n=35, 48%) (p=0.003). Moreover, 48% (n=13) of FASH-positive patients had CD4 below 100 cells/mm³. All patients tested had a negative result on k39 antigen test.

CONCLUSION

FASH was found to be a relevant diagnostic tool to detect signs of tuberculosis. Further research is needed to better define a patient profile suitable for investigation and also considering diagnostic accuracy.

Spatial accessibility to basic public health services in South Sudan

At independence in 2011, South Sudan's health sector was almost non-existent. The first national health strategic plan aimed to achieve an integrated health facility network that would mean that 70% of the population were within 5 km of a health service provider. Publically available data on functioning and closed health facilities, population distribution, road networks, land use and elevation were used to compute the fraction of the population within 1 hour walking distance of the nearest public health facility offering curative services. This metric was summarised for each of the 78 counties in South Sudan and compared with simpler metrics of the proportion of the population within 5 km of a health facility. In 2016, it is estimated that there were 1747 public health facilities, out of which 294 were non-functional in part due to the on-going civil conflict. Access to a service provider was poor with only 25.7% of the population living within one-hour walking time to a facility and 28.6% of the population within 5 km. These metrics, when applied sub-nationally, identified the same high priority, most vulnerable counties. Simple metrics based upon population distribution and location of facilities might be as valuable as more complex models of health access, where attribute data on travel routes are imperfect or incomplete and sparse. Disparities exist in South Sudan among counties and those with the poorest health access should be targeted for priority expansion of clinical services.

The Tortoise and the Hare: Guinea Worm, Polio and the Race to Eradication

Introduction: The eradication of a human infectious disease is a major challenge and, if achieved, represents a enormous achievement. This article explores the long and difficult journey towards eradication for polio and guinea worm.

Methods: The authors reviewed the programmatic approaches taken in the eradication strategies for these two diseases and the unique socio-political contexts in which these strategies are couched. The epidemiology of the last 15 years is compared and contrasted. The specific challenges for both programs are outlined and some key elements for success are highlighted.

Discussion: The success of these eradication programs is contingent upon many factors. Nothing is assured, and progress remains fragile and vulnerable to setbacks. Security must be ensured in guinea worm transmission areas in Africa and polio transmission areas in Pakistan and Afghanistan. Technical solutions alone cannot guarantee eradication. National leadership and continued international focus and support are necessary, today more than ever. The legacy of success would be extraordinary. It would reverberate to future generations in the same way that the eradication of smallpox does for this generation.

Association between exposure to traumatic events and anxiety disorders in a post-conflict setting: a cross-sectional community study in South Sudan

BACKGROUND

The negative effect of exposure to traumatic events on mental health is well known. Most studies of the effects of trauma on mental health in war-affected populations have focused on post-traumatic stress disorder (PTSD) and depression. Although some studies confirm the existence of anxiety symptoms in war-affected populations, the extent to which exposure to traumatic events is independently associated with anxiety diagnoses (other than PTSD) has received less attention. The study aimed to determine whether having an anxiety diagnosis, other than PTSD, was associated with experiencing traumatic events in a post-conflict setting, across genders and after controlling for demographic and socio-economic variables.

METHODS

In this cross-sectional community study (n = 1200), we applied the Harvard Trauma Questionnaire (HTQ) to investigate the extent of trauma exposure and PTSD. The Mini-International Neuropsychiatric Interview (MINI) was used to investigate the prevalence of anxiety disorders: generalized anxiety disorder (GAD), panic disorder (PD), social phobia, obsessive-compulsive disorder (OCD), and agoraphobia. Multinomial logistic regression analyses were conducted to examine the association between these disorders, previous trauma exposure, and socio-economic factors.

RESULTS

The participants were 56.4% male and 43.6% female. The age ranged between 18 and 73 years old (Mean 34.63, SD = 12.03). The estimated rates of GAD-only and PD-only (without comorbidity with PTSD) were 5.5% and 3.1%, respectively. Exposure to traumatic events and socio-economic disadvantage were significantly associated with having one or more anxiety diagnoses. After controlling for age, sex, rural/urban setting, and socio-economic disadvantage, exposure to trauma was independently associated with anxiety diagnosis. There were gender differences in the pattern of risk factors for having PTSD, GAD or PD.

CONCLUSION

In individuals with a history of war-related trauma exposure, attention should be given to symptoms of GAD and PD, in addition to PTSD symptoms.

Phylogenetic and ecologic perspectives of a monkeypox outbreak, southern Sudan, 2005

Identification of human monkeypox cases during 2005 in southern Sudan (now South Sudan) raised several questions about the natural history of monkeypox virus (MPXV) in Africa. The outbreak area, characterized by seasonally dry riverine grasslands, is not identified as environmentally suitable for MPXV transmission. We examined possible origins of this outbreak by performing phylogenetic analysis of genome sequences of MPXV isolates from the outbreak in Sudan and from differing localities. We also compared the environmental suitability of study localities for monkeypox transmission. Phylogenetically, the viruses isolated from Sudan outbreak specimens belong to a clade identified in the Congo Basin. This finding, added to the political instability of the area during the time of the outbreak, supports the hypothesis of importation by infected animals or humans entering Sudan from the Congo Basin, and person-to-person transmission of virus, rather than transmission of indigenous virus from infected animals to humans.