Reactive mass vaccination campaign against cholera in the COVID-19 context in Cameroon: challenges, best practices and lessons learned.

INTRODUCTION: since 1971, Cameroon is facing a growing series of cholera epidemics despite all the efforts made by the government to address this huge public health threat. In 2020, in addition to the COVID-19 pandemic, Cameroon recorded a high cholera case fatality rate of 4.3% following epidemics noted in the South, Littoral and South-West regions. The Cameroon Ministry of Public Health, has thus organized a reactive vaccination campaign against cholera to address the high mortality rate in the affected health districts of those regions. The objective of this study was to describe the challenges, best practices and lessons learned drawing from daily experiences from this reactive vaccination campaign against cholera. METHODS: we conducted a cross-sectional study drawn from the results of the campaign. We had a target population of 631,109 participants aged 1 year and above resident of the targeted health areas. RESULTS: the overall vaccination coverage was 64.4% with a refusal rate ranging from 0-10% according to health districts. Vaccination coverage was the lowest among people aged 20 years and above. The main challenge was difficulty maintaining physical distanciation, the main best practice was the screening of all actors taking part at the vaccination against COVID-19 and we found that emphasizing on thorough population sensitization through quarter heads and social mobilizers and adequately programming the campaign during a good climate season is crucial to achieving good vaccination coverage. CONCLUSION: lessons learned from this study could serve to inform various agencies in the event of planning rapid mass vaccination programs during pandemics.

A life in waiting: Refugees' mental health and narratives of social suffering after European Union border closures in March 2016.

RATIONALE: In 2015, an estimated 856,723 refugees, predominantly from Syria, Afghanistan, and Iraq arrived in Greece as an entry point into the European Union. The border of the Former Yugoslav Republic of Macedonia closed in March 2016, blocking a popular route for refugees through Europe, and left around 60,000 people stranded in Greece. OBJECTIVE: A mixed-method study was conducted among refugees in the regions of Attica, Epirus, and Samos between November 2016 and February 2017. The epidemiological survey showed that depending on study sites between 73% and 100% of the refugees suffered from anxiety disorder. The explanatory qualitative study aimed to understand refugees' mental health and narratives of social suffering in regards to experienced violence, the effect of current border closures, and the lack of an onward journey. METHOD: The explanatory qualitative study included 47 in-depth interviews and five focus group discussions with refugees purposely recruited through the concomitant epidemiological survey, representing both genders and a range of nationalities and ages. Data were thematically analysed to identify emergent patterns and categories using NVivo 11. RESULTS: The refugees overwhelmingly reported experiencing uncertainty and lack of control over their current life and future, which caused psychosocial distress and suffering. The passivity of life in refugee camps aggravated feelings of meaninglessness and powerlessness. The disruption of key social networks and absence of interactions with the surrounding Greek society led to feelings of isolation and being unwelcome. CONCLUSIONS: Refugees in Greece experience psychosocial distress and social suffering as a consequence of their uncertain and disrupted lives and the loss of social networks. Faster and transparent asylum procedures, the development of meaningful and empowering activities, and fostered social interactions with the surrounding society would contribute to alleviating their psychosocial suffering.

Cholera epidemic in Yemen, 2016-18: an analysis of surveillance data.

BACKGROUND: In war-torn Yemen, reports of confirmed cholera started in late September, 2016. The disease continues to plague Yemen today in what has become the largest documented cholera epidemic of modern times. We aimed to describe the key epidemiological features of this epidemic, including the drivers of cholera transmission during the outbreak. METHODS: The Yemen Health Authorities set up a national cholera surveillance system to collect information on suspected cholera cases presenting at health facilities. Individual variables included symptom onset date, age, severity of dehydration, and rapid diagnostic test result. Suspected cholera cases were confirmed by culture, and a subset of samples had additional phenotypic and genotypic analysis. We first conducted descriptive analyses at national and governorate levels. We divided the epidemic into three time periods: the first wave (Sept 28, 2016, to April 23, 2017), the increasing phase of the second wave (April 24, 2017, to July 2, 2017), and the decreasing phase of the second wave (July 3, 2017, to March 12, 2018). We reconstructed the changes in cholera transmission over time by estimating the instantaneous reproduction number, Rt. Finally, we estimated the association between rainfall and the daily cholera incidence during the increasing phase of the second epidemic wave by fitting a spatiotemporal regression model. FINDINGS: From Sept 28, 2016, to March 12, 2018, 1 103 683 suspected cholera cases (attack rate 3·69%) and 2385 deaths (case fatality risk 0·22%) were reported countrywide. The epidemic consisted of two distinct waves with a surge in transmission in May, 2017, corresponding to a median Rt of more than 2 in 13 of 23 governorates. Microbiological analyses suggested that the same Vibrio cholerae O1 Ogawa strain circulated in both waves. We found a positive, non-linear, association between weekly rainfall and suspected cholera incidence in the following 10 days; the relative risk of cholera after a weekly rainfall of 25 mm was 1·42 (95% CI 1·31-1·55) compared with a week without rain. INTERPRETATION: Our analysis suggests that the small first cholera epidemic wave seeded cholera across Yemen during the dry season. When the rains returned in April, 2017, they triggered widespread cholera transmission that led to the large second wave. These results suggest that cholera could resurge during the ongoing 2018 rainy season if transmission remains active. Therefore, health authorities and partners should immediately enhance current control efforts to mitigate the risk of a new cholera epidemic wave in Yemen. FUNDING: Health Authorities of Yemen, WHO, and Médecins Sans Frontières.

Highly targeted cholera vaccination campaigns in urban setting are feasible: The experience in Kalemie, Democratic Republic of Congo.

INTRODUCTION: Oral cholera vaccines are primarily recommended by the World Health Organization for cholera control in endemic countries. However, the number of cholera vaccines currently produced is very limited and examples of OCV use in endemic countries, and especially in urban settings, are scarce. A vaccination campaign was organized by Médecins Sans Frontières and the Ministry of Health in a highly endemic area in the Democratic Republic of Congo. This study aims to describe the vaccine coverage achieved with this highly targeted vaccination campaign and the acceptability among the vaccinated communities. METHODS AND FINDINGS: We performed a cross-sectional survey using random spatial sampling. The study population included individuals one year old and above, eligible for vaccination, and residing in the areas targeted for vaccination in the city of Kalemie. Data sources were household interviews with verification by vaccination card. In total 2,488 people were included in the survey. Overall, 81.9% (95%CI: 77.9-85.3) of the target population received at least one dose of vaccine. The vaccine coverage with two doses was 67.2% (95%CI: 61.9-72.0) among the target population. The vaccine coverage was higher during the first round (74.0, 95%CI: 69.3-78.3) than during the second round of vaccination (69.1%, 95%CI: 63.9-74.0). Vaccination coverage was lower in male adults. The main reason for non-vaccination was to be absent during the campaign. No severe adverse events were notified during the interviews. CONCLUSIONS: Cholera vaccination campaigns using highly targeted strategies are feasible in urban settings. High vaccination coverage can be obtained using door to door vaccination. However, alternative strategies should be considered to reach non-vaccinated populations like male adults and also in order to improve the efficiency of the interventions.

Cholera Epidemic in South Sudan and Uganda and Need for International Collaboration in Cholera Control.

Combining the official cholera line list data and outbreak investigation reports from the ministries of health in Uganda and South Sudan with molecular analysis of Vibrio cholerae strains revealed the interrelatedness of the epidemics in both countries in 2014. These results highlight the need for collaboration to control cross-border outbreaks.

Progress towards the UNAIDS 90-90-90 goals by age and gender in a rural area of KwaZulu-Natal, South Africa: a household-based community cross-sectional survey.

BACKGROUND: The Joint United Nations Programme on HIV/AIDS (UNAIDS) has developed an ambitious strategy to end the AIDS epidemic. After eight years of antiretroviral therapy (ART) program we assessed progress towards the UNAIDS 90-90-90 targets in Mbongolwane and Eshowe, KwaZulu-Natal, South Africa. METHODS: We conducted a cross-sectional household-based community survey using a two-stage stratified cluster probability sampling strategy. Persons aged 15-59 years were eligible. We used face-to-face interviewer-administered questionnaires to collect information on history of HIV testing and care. Rapid HIV testing was performed on site and venous blood specimens collected from HIV-positive participants for antiretroviral drug presence test, CD4 count and viral load. At the time of the survey the CD4 threshold for ART initiation was 350 cells/µL. We calculated progression towards the 90-90-90 UNAIDS targets by estimating three proportions: HIV positive individuals who knew their status (first 90), those diagnosed who were on ART (second 90), and those on ART who were virally suppressed (third 90). RESULTS: We included 5649/6688 (84.5%) individuals. Median age was 26 years (IQR: 19-40), 62.3% were women. HIV prevalence was 25.2% (95% CI: 23.6-26.9): 30.9% (95% CI: 29.0-32.9) in women; 15.9% (95% CI: 14.0-18.0) in men. Overall progress towards the 90-90-90 targets was as follows: 76.4% (95% CI: 74.1-78.6) knew their status, 69.9% (95% CI: 67.0-72.7) of those who knew their status were on ART and 93.1% (95% CI: 91.0-94.8) of those on ART were virally suppressed. By sex, progress towards the 90-90-90 targets was: 79%-71%-93% among women; and 68%-68%-92% among men (p-values of women and men comparisons were < 0.001, 0.443 and 0.584 respectively). By age, progress was: 83%-75%-95% among individuals aged 30-59 years and 64%-58%-89% among those aged 15-29 years (p-values of age groups comparisons were < 0.001, < 0.001 and 0.011 respectively). CONCLUSIONS: In this context of high HIV prevalence, significant progress has been achieved with regards to reaching the UNAIDS 90-90-90 targets. The third 90, viral suppression in people on ART, was achieved among women and men. However, gaps persist in HIV diagnosis and ART coverage particularly in men and individuals younger than 30 years. Achieving 90-90-90 is feasible but requires additional investment to reach youth and men.

Dried Blood Spots for Measuring Vibrio cholerae-specific Immune Responses.

BACKGROUND: Vibrio cholerae causes over 2 million cases of cholera and 90,000 deaths each year. Serosurveillance can be a useful tool for estimating the intensity of cholera transmission and prioritizing populations for cholera control interventions. Current methods involving venous blood draws and downstream specimen storage and transport methods pose logistical challenges in most settings where cholera strikes. To overcome these challenges, we developed methods for determining cholera-specific immune responses from dried blood spots (DBS). METHODOLOGY/PRINCIPAL FINDINGS: As conventional vibriocidal assay methods were unsuitable for DBS eluates from filter paper, we adopted a drop-plate culture method. We show that DBS collected from volunteers in South Sudan, and stored for prolonged periods in field conditions, retained functional vibriocidal antibodies, the titers of which correlated with paired serum titers determined by conventional spectrophotometric methods (r = 0.94, p = 0.00012). We also showed that eluates from DBS Serum Separator cards could be used with conventional spectrophotometric vibriocidal methods, and that they correlated with paired serum at a wide range of titers (r = 0.96, p<0.0001). Similarly, we used ELISA methods to show that V. cholerae O-specific polysaccharide antibody responses from DBS eluates correlated with results from paired serum for IgG (r = 0.85, p = 0.00006), IgM (r = 0.79, p = 0.00049) and IgA (r = 0.73, p = 0.0019), highlighting its potential for use in determination of isotype-specific responses. Storage of DBS cards at a range of temperatures did not change antibody responses. CONCLUSION: In conclusion, we have developed and demonstrated a proof-of-concept for assays utilizing DBS for assessing cholera-specific immune responses.

High Prevalence of Shigella or Enteroinvasive Escherichia coli Carriage among Residents of an Internally Displaced Persons Camp in South Sudan.

Displaced persons living in camps are at an increased risk of diarrheal diseases. Subclinical carriage of pathogens may contribute to the spread of disease, especially for microbes that require a low infectious dose. Multiplex real-time polymerase chain reaction was performed to detect a panel of 20 bacterial, viral, and protozoal targets, and we report a high prevalence of enteropathogen carriage, including Shigella spp. or enteroinvasive Escherichia coli in 14%, among a sample of 88 asymptomatic individuals in an internally displaced persons camp in South Sudan. Further studies are needed to determine the contribution of such carriage to the spread of disease.

High Hepatitis E Seroprevalence Among Displaced Persons in South Sudan.

AbstractLarge protracted outbreaks of hepatitis E virus (HEV) have been documented in displaced populations in Africa over the past decade though data are limited outside these exceptional settings. Serological studies can provide insights useful for improving surveillance and disease control. We conducted an age-stratified serological survey using samples previously collected for another research study from 206 residents of an internally displaced person camp in Juba, South Sudan. We tested serum for anti-HEV antibodies (IgM and IgG) and estimated the prevalence of recent and historical exposure to the virus. Using data on individuals' serostatus, camp arrival date, and state of origin, we used catalytic transmission models to estimate the relative risk of HEV infection in the camp compared with that in the participants' home states. The age-adjusted seroprevalence of anti-HEV IgG was 71% (95% confidence interval = 63-78), and 4% had evidence of recent exposure (IgM). We estimated HEV exposure rates to be more than 2-fold (hazard ratio = 2.3, 95% credible interval = 0.3-5.8) higher in the camp than in the participants' home states, although this difference was not statistically significant. HEV transmission may be higher than previously appreciated, even in the absence of reported cases. Improved surveillance in similar settings is needed to understand the burden of disease and minimize epidemic impact through early detection and response.

Retrospective mortality among refugees from the Central African Republic arriving in Chad, 2014.

BACKGROUND: The Central African Republic has known long periods of instability. In 2014, following the fall of an interim government installed by the Séléka coalition, a series of violent reprisals occurred. These events were largely directed at the country's Muslim minority and led to a massive displacement of the population. In 2014, we sought to document the retrospective mortality among refugees arriving from the CAR into Chad by conducting a series of surveys. METHODS: The Sido camp was surveyed exhaustively in March-April 2014 and a systematic sampling strategy was used in the Goré camp in October 2014. The survey recall period began November 1, 2013, just before the major anti-Balaka offensive. Heads of households were asked to describe their household composition at the beginning of and throughout the recall period. For household members reported as dying, further information about the date and circumstances of death was obtained. RESULTS: In Sido, 3449 households containing 25 353 individuals were interviewed. A total of 2599 deaths were reported, corresponding to a crude mortality rate of 6.0/10000 persons/day, and 8% of the population present at the beginning of the recall period died. Most (82.4%) deaths occurred among males, most deaths occurred in December 2013 and January 2014, and 92% were due to violence in the CAR. In Goré, 1383 households containing 8614 individuals were interviewed. A total of 1203 deaths were reported, corresponding to a crude mortality rate of 3.7/10000 persons/day [95%CI 3.5-3.9], and 12% of the population present at the beginning of the recall period died. Most (77.1%) deaths occurred among males. As in Sido, most deaths occurred in December 2013 and January 2014, and 86% of all deaths were due to violence in the CAR. CONCLUSIONS: The results of these two surveys describe a part of the toll of the violent events of December 2013 and January 2014 in the Central African Republic.

Intermittent preventive treatment for malaria among children in a refugee camp in Northern Uganda: lessons learned.

Northern Uganda hosts a large population of refugees from South Sudan, and malaria is one of the major health problems in the area. In 2015, intermittent preventive treatment for malaria (IPTc) was implemented in two refugee camps among children aged 6 months to 14 years. Three distributions of dihydroartemisinin-piperaquine (DP) were conducted at 8-week intervals. The first dose was directly administered at IPTc distribution sites and the second and third doses were given to caregivers to administer at home. A multi-faceted evaluation was implemented, including coverage surveys, malaria prevalence surveys, reinforced surveillance, and pharmacovigilance. Programme coverage exceeded 90% during all three distributions with a total of 40,611 participants. Compared to same period during the previous year (only available data), the incidence of malaria in the target populations was reduced (IRR 0.73, 95% CI 0.69-0.77 among children under 5 years old; IRR 0.70, 95% CI 0.67-0.72 among children aged 5-14 years). Among those not targeted for intervention, the incidence between the 2 years increased (IRR 1.49, 95% CI 1.42-1.56). Cross-sectional surveys showed a prevalence of parasitaemia (microscopy or PCR) of 12.9-16.4% (95% CI 12.6-19.3) during the intervention, with the highest prevalence among children aged 5-14 years, but with a large increase 8 weeks after the final distribution. A total of 57 adverse events were reported during the intervention period, including one severe adverse event (death from varicella). Adverse events were of mild to moderate severity, and were mainly dermatologic and gastrointestinal. This is the first documentation of an IPTc programme in a refugee camp. The positive impact of DP on the incidence of malaria, together with its favourable safety profile, should lead to further use of IPTc in similar settings. Expanding coverage groups and decreasing intervals between distributions might provide more benefit, but would need to be balanced with the operational implications of a broader, more frequent distribution schedule.

Quantitative survey on health and violence endured by refugees during their journey and in Calais, France.

Background: In 2015, more than 1 million refugees arrived in Europe. During their travels, refugees often face harsh conditions, violence and torture in transit countries, but there is a lack of quantitative evidence on their experiences. We present the results of a retrospective survey among refugees in the 'Jungle' of Calais, France, to document their health problems and the violence they endured during their journeys. Methods: We conducted a cross-sectional population-based survey in November and December 2015. The sample size was set at 402 individuals, and geospatial simple random sampling was used. We collected data on demographics, routes travelled, health status, violence and future plans. Results: Departures from the country of origin increased beginning in September 2015. Sixty-one percent of respondents reported having at least one health problem, especially while in Calais. Overall, 65.6% (95% CI 60.3-70.6) experienced at least one violent event en route; 81.5% of refugees wanted to go to the UK. Conclusions: This first quantitative survey conducted among refugees in Europe provides important socio-demographic data on refugees living in Calais and describes the high rate of violence they encountered during their journeys. Similar documentation should be repeated throughout Europe in order to better respond to the needs of this vulnerable population.

Immune Responses to an Oral Cholera Vaccine in Internally Displaced Persons in South Sudan.

Despite recent large-scale cholera outbreaks, little is known about the immunogenicity of oral cholera vaccines (OCV) in African populations, particularly among those at highest cholera risk. During a 2015 preemptive OCV campaign among internally displaced persons in South Sudan, a year after a large cholera outbreak, we enrolled 37 young children (1-5 years old), 67 older children (6-17 years old) and 101 adults (≥18 years old), who received two doses of OCV (Shanchol) spaced approximately 3 weeks apart. Cholera-specific antibody responses were determined at days 0, 21 and 35 post-immunization. High baseline vibriocidal titers (>80) were observed in 21% of the participants, suggesting recent cholera exposure or vaccination. Among those with titers ≤80, 90% young children, 73% older children and 72% adults seroconverted (≥4 fold titer rise) after the 1st OCV dose; with no additional seroconversion after the 2nd dose. Post-vaccination immunological endpoints did not differ across age groups. Our results indicate Shanchol was immunogenic in this vulnerable population and that a single dose alone may be sufficient to achieve similar short-term immunological responses to the currently licensed two-dose regimen. While we found no evidence of differential response by age, further immunologic and epidemiologic studies are needed.

Who Needs to Be Targeted for HIV Testing and Treatment in KwaZulu-Natal? Results From a Population-Based Survey.

INTRODUCTION: Identifying gaps in HIV testing and treatment is essential to design specific strategies targeting those not accessing HIV services. We assessed the prevalence and factors associated with being HIV untested, unaware, untreated, and virally unsuppressed in KwaZulu-Natal, South Africa. METHODS: Cross-sectional population-based survey. People aged 15-59 years were eligible. Interviews, HIV testing, and blood collection for antiretroviral drug presence test, CD4, and viral load were done at the participants' home. RESULTS: Of the 5649 individuals included, 81.4% (95% CI: 79.8 to 82.9) had previously been tested. HIV prevalence was 25.2%. HIV-positivity awareness rate was 75.2% (95% CI: 72.9 to 77.4). Of all unaware, 73.3% of people were aged <35 years and 68.7% were women. Antiretroviral therapy coverage was 75.0% (95% CI: 72.0 to 77.8) among those eligible for treatment (CD4 < 350, PMTCT-B) and 53.1% (95% CI: 50.4 to 55.7) among all HIV-positive individuals. Viral load was <1000 copies per milliliter in 57.1% of all HIV-positive individuals. Although 66.3% and 71.7% of people with viral load ≥1000 copies per milliliter were people aged <35 years and women respectively, men had 4.4, 1.8, 1.6, and 1.7 times the odds of being untested, unaware, untreated, and virally unsuppressed. In addition, people with more than 1 sexual partner had 1.3, 2.2, and 1.9 times the odds of being untested, unaware, and untreated. CONCLUSIONS: The majority of HIV-positive people unaware of their status, untreated, and virally unsuppressed were individuals aged <35 years and women. However, men were disproportionately untested, unaware HIV positivity, untreated, and virally unsuppressed. In this context, HIV testing and treatment should be prioritized to target young people and women, whereas novel strategies are necessary to reach men.