Enhanced surveillance for adverse events following immunization during the 2019 typhoid conjugate vaccine campaign in Harare, Zimbabwe.

BACKGROUND: During February 25-March 4, 2019, Zimbabwe's Ministry of Health and Child Care conducted an emergency campaign using 342,000 doses of typhoid conjugate vaccine (TCV) targeting individuals 6 months-15 years of age in eight high-risk suburbs of Harare and up to 45 years of age in one suburb of Harare. The campaign represented the first use of TCV in Africa outside of clinical trials. METHODS: Three methods were used to capture adverse events during the campaign and for 42 days following the last dose administered: (1) active surveillance in two Harare hospitals, (2) national passive surveillance, and (3) a post-campaign coverage survey. RESULTS: Thirty-nine adverse events were identified during active surveillance, including 19 seizure cases (16 were febrile), 16 hypersensitivity cases, 1 thrombocytopenia case, 1 anaphylaxis case, and two cases with two conditions. Only 21 (54%) of 39 patients were hospitalized and 38 recovered without sequelae. Attack rates per 100,000 TCV doses administered were highest for seizures (6.27) and hypersensitivity (5.02). Only 6 adverse events were reported through passive surveillance by facilities other than the two active surveillance hospitals. A total of 177 (10%) of 1,817 vaccinees surveyed reported experiencing an adverse event during the post-campaign coverage survey, of which 25 (14%) sought care. CONCLUSIONS: In line with previous evaluations of TCV, enhanced adverse event monitoring during an emergency campaign supports the safety of TCV. The majority of reported events were minor or resulted in recovery without long-term sequelae. Attack rates for seizures and hypersensitivity were low compared with previous active surveillance studies conducted in Kenya and Burkina Faso. Strengthening adverse event monitoring in Zimbabwe and establishing background rates of conditions of interest in the general population may improve future safety monitoring during new vaccine introductions.

Cost of human papillomavirus vaccine delivery at district and health facility levels in Zimbabwe: A school-based vaccination program targeting multiple cohorts.

BACKGROUND: After a pilot project in 2014-15 Zimbabwe introduced the human papillomavirus (HPV) vaccine nationally in 2018 for girls aged 10-14 years through a primarily school-based vaccination campaign with two doses administered at 12-month intervals. In 2019, a first dose was delivered to a new cohort of girls in grade 5 of girls age 10 years if out-of-school (OOS), along with a second dose to the 2018 multiple cohorts. Additional effort was made to identify and mobilize OOS girls by Village Health Workers (VHWs) in the community. Zimbabwe reported 1,569,905 doses of HPV vaccine administered during the 2018 and 2019 campaigns. This analysis evaluated the cost of Zimbabwe's national HPV vaccine introduction. METHODS: A retrospective, incremental, ingredients-based cost analysis from the provider perspective was conducted in 2018 and 2019. Financial and economic cost data were collected at district and health facility levels using a two-stage cluster sampling approach and four cost dimensions: program activity, resource input, payer, and administrative level. Costs are presented in 2020 US$ in total and per dose. RESULTS: The total weighted costs for combined district and health facility administrative levels were US$ 828,731 (financial) and US$ 2,060,943 (economic). For service delivery, the total weighted cost per dose was US$ 0.16 (financial) and US$ 0.59 (economic). The program activities with the largest share of total weighted financial cost were training (37% of total) and service delivery (30%), while the largest shares of total weighted economic costs were service delivery (45%) and training (19%). Efforts by VHWs to reach OOS girls resulted in an additional US$ 2.99 in financial cost per dose and US$ 7.79 in economic cost per dose. CONCLUSION: The service delivery cost per dose was lower than that documented in the pilot program cost analysis in Zimbabwe and studies elsewhere, reflecting a campaign delivery approach that spread fixed costs over a large vaccination cohort. The additional cost of reaching OOS girls with the HPV vaccine was documented for the first time in low- and middle-income countries, which may provide information on potential costs for other countries.

Nationwide introduction of HPV vaccine in Zimbabwe 2018-2019: Experiences with multiple cohort vaccination delivery.

The World Health Organization (WHO) recommends the human papillomavirus (HPV) vaccine for girls aged 9-14 years for cervical cancer prevention and encourages vaccinating multiple cohorts in the first year to maximize impact. The HPV vaccine was introduced nationwide in Zimbabwe in 2018 through a 1-week school-based campaign to multiple cohorts (all girls 10-14 years old), followed by a single cohort (grade 5 girls in school and age 10 girls out-of-school) in 2019. During the 2019 campaign, the multiple cohort's second dose was concurrently delivered with the single cohort's first dose. We interviewed national-level key informants, reviewed written materials, and observed vaccination sessions to document HPV vaccine introduction in Zimbabwe and identify best practices and challenges. Key informants included focal persons from government health and education ministries, in-country immunization partners, and HPV Vaccine Strategic Advisory Group members. We conducted a desk review of policy/strategy documents, introduction plans, readiness reports, presentations, and implementation tools. Vaccination sessions were observed in three provinces during the 2019 campaign. Key informants (n = 8) identified high cervical cancer burden, political will, vaccine availability, donor financing, and a successful pilot program as factors driving the decision to introduce the HPV vaccine nationally. The school-based delivery strategy was well accepted, with strong collaboration between health and education sectors and high community demand for vaccine identified as key contributors to this success. Challenges with transitioning from a multiple age-based to single grade- and age-based target population as well as funding shortages for operational costs were reported. Zimbabwe's first multiple cohort, school-based HPV vaccination campaign was considered successful-primarily due to strong collaboration between health and education sectors and political commitment; however, challenges vaccinating overlapping cohorts in the 2019 campaign were observed. Integration with existing health and vaccination activities and continued resource mobilization will ensure sustainability of Zimbabwe's HPV vaccination program in the future.

HPV vaccination coverage in three districts in Zimbabwe following national introduction of 0,12 month schedule among 10 to 14 year old girls.

BACKGROUND: Zimbabwe has one of the highest incidence rates of cervical cancer in the world - 61.7 per 100,000 women. The government of Zimbabwe introduced bivalent HPV vaccine with a 0,12 month schedule to all 10-14 year old girls using a pulsed-campaign approach in May 2018 (dose 1) and May 2019 (dose 2). METHODS: In August 2019, we conducted a population-based, two-stage cluster survey of households with girls who were eligible for the national HPV vaccination program to determine two-dose HPV vaccination coverage in three districts of Zimbabwe. All households with girls currently aged 11 to 15 years were line-listed through a census conducted in the pre-selected clusters from each district prior to survey administration. A simple random sample of eligible households was selected from these lists to estimate HPV vaccine coverage at sufficient power with a margin of error of +/- 5%. Criteria for district selection included estimated vaccine uptake (low, medium, high), rural/urban/peri-urban, geographic area, estimated number of girls not in school, and recent natural disasters or disease outbreaks. We oversampled households with girls aged 13 or 14 years at the time of dose 1. RESULTS: On-time dose 1 uptake ranged from 88 to 94% and two-dose HPV vaccine coverage ranged from 75 to 86% across the three districts. Nearly all vaccinations occurred in schools, and less than 2% of girls did not attend school. There were challenges assessing ages of girls at schools prior to vaccination - 9% of girls vaccinated were less than 10 years old at time of dose 1. DISCUSSION: Zimbabwe has demonstrated that high uptake and successful completion of 2-dose HPV vaccination can be achieved with an annual dosing schedule. Efforts going forward will need to focus on minimizing dropout between doses and routinizing annual vaccinations in schools for every subsequent new cohort of eligible girls in the country.

Distribution of rotavirus genotypes associated with acute diarrhoea in Zimbabwean children less than five years old before and after rotavirus vaccine introduction.

BACKGROUND: Sentinel surveillance for diarrhoea is important to monitor changes in rotavirus epidemiological trends and circulating genotypes among children under 5 years before and after vaccine introduction. The Zimbabwe Ministry of Health and Child Care introduced rotavirus vaccine in national immunization program in May 2014. METHODS: Active hospital-based surveillance for diarrhoea was conducted at 3 sentinel sites from 2008 to 2016. Children aged less than 5 years, who presented with acute gastroenteritis as a primary illness and who were admitted to a hospital ward or treated at the emergency unit, were enrolled and had a stool specimen collected and tested for rotavirus by enzyme immunoassay (EIA). Genotyping of positive stools was performed using reverse-transcription polymerase chain reaction and genotyping assays. Pre-vaccine introduction, 10% of all positive stool specimens were genotyped and all adequate positive stools were genotyped post-vaccine introduction. RESULTS: During the pre-vaccine period, a total of 6491 acute gastroenteritis stools were collected, of which 3016 (46%) tested positive for rotavirus and 312 (10%) of the rotavirus positive stools were genotyped. During the post-vaccine period, a total of 3750 acute gastroenteritis stools were collected, of which 937 (25%) tested positive for rotavirus and 784 (84%) were genotyped. During the pre-vaccine introduction the most frequent genotype was G9P[8] (21%) followed by G2P[4] (12%), G1P[8] (6%), G2P[6] (5%), G12P[6] (4%), G9P[6] (3%) and G8P[4] (3%). G1P[8] (30%) was most dominant two years after vaccine introduction followed by G9P[6] (20%), G2P[4] (15%), G9P[8] (11%) and G1P[6] (4%). CONCLUSION: The decline in positivity rate is an indication of early vaccine impact. Diversity of circulating strains underscores the importance of continued monitoring and strain surveillance after vaccine introduction.

Factors influencing infant-feeding choices selected by HIV-infected mothers: perspectives from Zimbabwe.

AIM: To assess factors influencing infant-feeding methods selected by HIV-infected mothers. METHODS: A descriptive quantitative study was conducted among 80 mothers with babies aged 0-6 months who were randomly selected and interviewed. Descriptive statistics were used to summarize the findings. RESULTS: Factors considered by women in choosing the infant-feeding methods included sociocultural acceptability (58.8%), feasibility and support from significant others (35%), knowledge of the selected method (55%), affordability (61.2%), implementation of the infant-feeding method without interference (62.5%), and safety (47.5%). Exclusive breast-feeding was the most preferred method of infant feeding. Disclosure of HIV status by a woman to her partner is a major condition for successful replacement feeding method, especially within the African cultural context. However, disclosure of HIV status to the partner was feared by most women as only 16.2% of the women disclosed their HIV status to partners. CONCLUSION: The factors considered by women in choosing the infant-feeding option were ability to implement the options without interference from significant others, affordability, and sociocultural acceptability. Knowledge of the selected option, its advantages and disadvantages, safety, and feasibility were also important factors. Nurses and midwives have to educate clients and support them in their choice of infant-feeding methods.