Malaria outbreak investigation in a rural area south of Zimbabwe: a case–control study

Abstract

Background Ninety percent of the global annual malaria mortality cases emanate from the African region. About 80–90% of malaria transmissions in sub-Saharan Africa occur indoors during the night. In Zimbabwe, 79% of the population are at risk of contracting the disease. Although the country has made significant progress towards malaria elimination, isolated seasonal outbreaks persistently resurface. In 2017, Beitbridge District was experiencing a second malaria outbreak within 12 months prompting the need for investigating the outbreak. Methods An unmatched 1:1 case–control study was conducted to establish the risk factors associated with contracting malaria in Ward 6 of Beitbridge District from week 36 to week 44 of 2017. The sample size constituted of 75 randomly selected cases and 75 purposively selected controls. Data were collected using an interviewer-administered questionnaire and Epi Info version 7.2.1.0 was used to conduct descriptive, bivariate and multivariate analyses of the factors associated with contracting malaria. Results Fifty-two percent of the cases were females and the mean age of cases was 29 ± 13 years. Cases were diagnosed using rapid diagnostic tests. Sleeping in a house with open eaves (OR: 2.97; 95% CI 1.44–6.16; p < 0.01), spending the evenings outdoors (OR: 2.24; 95% CI 1.04–4.85; p = 0.037) and sleeping in a poorly constructed house (OR: 4.33; 95% CI 1.97–9.51; p < 0.01) were significantly associated with contracting malaria while closing eaves was protective (OR: 0.45; 95% CI 0.20–1.02; p = 0.055). After using backward stepwise logistic regression, sleeping in a poorly constructed house was associated with five-fold odds of getting sick from malaria (AOR: 8.40; 95% CI 1.69–41.66; p = 0.009). Those who had mosquito nets did not use them consistently. The district health team and the rural health centre were well prepared to response despite having limited human resources. Conclusion Health promotion messages should emphasize the importance of closing the entry points of the malaria vector, and the construction of better houses in the future. Residents had to be educated in the importance of consistent use of mosquito nets. The district had to improve malaria preventive measures like distribution of mosquito nets and lobby for more human resources to assist with malaria surveillance thus, curbing the recurrence of malaria outbreaks.

Factors associated with a malaria outbreak at Tongogara refugee camp in Chipinge District, Zimbabwe, 2021: a case–control study

“…Gaps provide an entry route for mosquitoes into to the house which increases the risk of contracting malaria. These findings are consistent with Mundagowa and Chimberengwa, who found that sleeping in a poorly constructed house with open eaves increased malaria risk [ 17 ]. Yaro et al concluded that improving the construction of houses to include screened windows, closing eaves and solid roofs may reduce malaria incidence [ 18 ].…”

“…The WHO recommends the provision, use and timely replacement of LLINs [ 24 ]. While this is core intervention, LLINs are only effective if used consistently, hence the need for continued health education [ 17 ]. The provision of nets for outdoor spaces in combination with IRS among this population may be effective in reducing the incidence of malaria.…”

Temporal and spatial analysis of Plasmodium falciparum genomics reveals patterns of connectivity in a low-transmission district in Southern Province, Zambia

“…Identifying suspected imported cases (where a genetically distinct parasite is introduced to a region) would assist malaria control programs in identifying high-trafficked routes of human movement and sources of importation (Tessema et al, 2019). Blocking such cases would also be key to protect against introductions to populations which are increasingly more susceptible to malaria after successful control efforts (Mundagowa and Chimberengwa, 2020;Patel et al, 2014).…”

Factors associated with a malaria outbreak at Tongogara Refugee Camp in Chipinge District, Zimbabwe, 2021: A case-control study

“…The distribution of nets for outdoor sleeping spaces among populations that are prone to sleeping outside during summer is recommended according to the Zimbabwe National Malaria Programme (21). Insecticide-treated nets are only effective if used consistently (22).…”