This study provides the first baseline data on the epidemiological parameters, characteristics of plasmodial infection, and the knowledge and prevention practices regarding malaria residents in a vulnerable population of the Nyanga province in Gabon.
In this cross-sectional survey, 1,307 individuals composed of women of childbearing age and children under 5 years old were included.
This unprecedented study provides baseline data on epidemiological parameters, characteristics of plasmodial infection, and the knowledge and prevention practices regarding malaria residents in a vulnerable population of Nyanga Province in Gabon.
The vast majority of respondents (97.7%) in Nyanga province (rural area) was aware of malaria. Similar results have been reported in other studies in other countries [8–11].
In our study, we showed that our study population had adequate knowledge regarding the mosquito bite as the means of transmission. Our results also demonstrate that fever, and headache, fatigue and aches were correctly identified as symptoms of malaria which corroborates results from similar studies conducted in Cameroon, Ethiopia and Tanzania [8, 9, 12] where respondents were able to name at least one symptom of malaria.
National malaria programs need to know how and where their populations obtain information regarding malaria in order to better plan their communication activities. Our study revealed that most of the population obtains information on malaria from media source and, to a lesser extent, from hospitals and health centers. Given the young mean age of the interviewed women (334.05 ± 129.54 months), these results are to be expected as, in Gabon, the majority of young people watch television and are connected to social media via the internet. These findings are different from those obtained in another study led in India  in which overall, hospitals, health centers or doctors were the most frequently cited interpersonal source of information about malaria. This disparity could be explained by the difference in age of the women included in the different studies. These results also highlight the need for public health professionals to work together with media, as well as hospital facilities and doctors, to disseminate accurate and reliable malaria information and use age-appropriate means of communication in order to have the most impact.
Respondents showed adequate knowledge in regards to bed nets, spraying of insecticides and environmental sanitation as effective prevention strategies. Over 95% of people interviewed in Nyanga Province reported using bed nets to prevent malaria. Indeed, in Gabon and in other countries of Central Africa, the national policy strategies against malaria relies on the use of Insecticide-treated bed nets. During this last decade, a concerted campaign against malaria has led to unprecedented levels of interventions across sub-Saharan Africa . African governments and decision-makers in the health sector are in the habit of conducting mass awareness campaign promotion through audiovisual networks, social networks and newspapers. School age children usually are educated about malaria in school. Although these campaigns take place throughout the year, they are more emphasized during the internationally celebrated malaria awareness day. Also in Gabon, as other Malaria endemic countries, insecticide-treated bed nets are freely distributed to pregnant women and children under 5 years, as is intermittent preventive treatment for pregnant women, Indoor residual spraying is also now being widely used across Africa with increasing amounts of coverage achieved [5, 15]. Our results on measures of prevention are similar to those obtained in a recent study led in Cameroon and in Gabon [11, 16].. In our study, some respondents believed that Malaria infection was caused by getting wet in the rain. These findings are not surprising as it has been shown in another of our study that some people associate fever from getting wet in the rain with malaria (data not published).
Our study showed a malaria infection lower (13.6%) than in other rural area (Makokou 53.6%, Lastoursville 79.5%, Oyem 44.2%) [6, 17]. In these studies, the tested study population was in based in hospitals while our study tested the general population providing an explanation for the low prevalence of malaria infection in the present study. Our low prevalence of malaria infection could also be associated with the high level of knowledge of preventive measures in our study area. . The distribution of the malaria prevalence among the five departments of the Nyanga province was quite varied. The departments of Tchibanga and Moabi had a prevalence of 18.7% and 14.8% respectively, the highest prevalence for malaria parasite. The departments of Moulengui-Binza and Mabanda both showed parasite prevalence lower than 10% while in the department of Mayumba, malaria parasite was not at all detected. This variation between departments could be explained by some factors such as the population density. In fact, Tchibanga main town of the Nyanga province which comprises of more than half of the total population in that geographical area. It was surprising that none of 188 participants that were tested in Mayumba were positive for malaria infection since Gabon is hyperendemic for malaria.
The overall prevalence of the plasmodial infection was significantly higher in children and pregnant women compared to adults in the cities of Tchibanga and Moabi. It has been reported that prevalence was more common for school-aged children compared to other groups, including under-fives who, together with pregnant women, are still considered to be at highest risk of malaria
The protective efficacy of ITNs is defined as the proportion of human exposure to malaria vectors prevented by ITN use out of total exposure i.e. compared to a non-user . In our study, the prevalence of infected individuals sleeping under mosquito nets and using insecticides was similar to that of uninfected persons who do not sleep on a net and do not use insecticides. The similar proportions of Plasmodium-infected individuals, sleeping under mosquito nets and non-infected individuals with non-mosquito-borne plasmodia may indicate that Plasmodium infection is more likely to occur during waking hours than during sleep hours.