A total of 1,307 participants were recruited in this study, originating from 535 homes. Included in the study were 631 women of childbearing age, including sixty-one (61) pregnant women, and 676 children. Data were available only for 1296 participants. The pregnancy status and the number of months of pregnancy of the women was self-reported and no confirmatory pregnancy tests were carried out.
Clinical and socio-demographic characteristics of the studied population
All participants were residents of the Nyanga Province. The mean age of interviewed study participants was 27.8 ±11 months.
On average, there were 7.45 ± 3.50 people per household, including 1.95 ± 1.34 children and 0.17 ± 0.43 pregnant women with an average of 5.51 ± 2. 58 months of pregnancy. About 162 out of 1299 (12. 5%) were febrile (axillary temperature > 37. 5 °C) and 7. 5% (97/1296) had history of fever in the last 14 days prior to sampling. The general description of participants is shown in Table 1.
General knowledge on malaria causes, symptoms and prevention
Almost the entire interviewed population previously heard about malaria (97.7%) and attributed the cause of malaria to a mosquito bite (95.7%, 617/649). The majority of the respondents (96.2%, (624/649) also thought that they could get malaria by walking in the rain. Some respondents (17.3%, (112/649) believed malaria to be transmitted by ingesting of dirty water, and finally, (8.3% (54/649) of the studied population thought that malaria was transmitted sexually. The most commonly known clinical symptoms by the respondents were, fever (88.7%), body aches (78.3%), headache (74.1%), fatigue (71.3%), vomiting (49.69%), cough (21.9%), diarrhea (20.1%), and stomachaches (19.8%)
Knowledge and action for malaria prevention and vector control were also evaluated. The majority of the interviewed individuals thought that the use of bed nets at home and environmental sanitation (95.06% and 84.57%, respectively) could prevent malaria. More than half of the respondents thought that spraying insecticides could also prevent malaria (64.7%). Less than half of the respondents thought that vaccination and washing their hands before eating (64.5% and 49.9%, respectively) could also be ways to prevent malaria.
The interviewed people who had already heard of malaria reported receiving information on malaria from one or more sources. The sources of information were varied and are reported in Table 2. Among the different sources of information, the largest proportion of respondents had received information regarding malaria from a media source (67.7%), followed by hospitals, health center or doctors (22.9%). The sources least reported were schools and sensitization campaigns (2.6%). Among media sources television and social media were a major source of malaria information for all respondents.
This survey revealed that the rate of reported bednet use was 73.3% (924/1260). Insecticide spraying was used by 52.1% (574/1103) of the subjects. Fans were more commonly used according to this study than air-conditioners (58.4%, versus 3.2%, p<0.05). More than half of the women had not received an Insecticide-Treated bed Nets (ITN) during antenatal visits of their last pregnancy. Sixty-six percent (66.1%) of women said that Long Lasting Insecticide Nets (LLIN) is free in public health facilities, but 26.1% reported that it was not free. As for intermittent preventive treatment with Sulfadoxine-Pyrimethamine (IPT-SP), 50.2% of women said that IPT-SP is free in public health facilities, whereas 32.6% of them stated it was not.
Characteristics of plasmodial infection
The overall prevalence of plasmodial infection diagnosed with RDT was 13.9% (180/1296). It was significantly different between department capitals (p <0.05). The prevalence of Plasmodium infection was higher in Tchibanga [18.7% (145/776)] compared to Moulingui-Binza [9.2% (8/87)], (p = 0.02) and Mabanda [3,6% (3/83)], (p = 0.0005). In Moabi, the prevalence of plasmodial infection [14.8% (24/162)] was higher than in Mabanda [3.6% (3/83)], (p = 0.008). There was no plasmodial infection diagnosis in Mayumba. The overall prevalence of plasmodial infection was 16.5% (111/674) in children ≤ 5 years old, 10.2% (57/558) in women of childbearing age, and 20.0% (12/60) in pregnant women. The difference in prevalence of plasmodial infection between children, women of childbearing age, and pregnant women was significant in the surveyed sites (p = 0.01). The prevalence of plasmodial infection between these same groups was also significantly different in Tchibanga and Moabi (p = 0.007, p = 0.006, respectively). In addition, the prevalence of infection was significantly different between age groups in women of childbearing age. Women between 11 to 20 years of age (37.50%) were more infected than women in other age groups (p=0.012). Table 2 and Figure 2 show a summary of the general characterization of the plasmodial infection by department capitals. There was no statistically significant difference in the rates of bednet use and of insecticide use between infected and uninfected study participants (p>0.05), as shown in Figure 3.