This is the first nationally representative study to compare ITN usage in children under 5 years old living in households that owned at least one ITN between 2010 and 2015 following the nationwide ITN distribution campaign in 2012. Despite similar ITN access rates between the two surveys (38% for 2010 and 39% for 2015) , the rate of ITN usage in children under 5 years old increased from 57.8% in 2010 to 69.0% in 2015. Moreover, the study revealed that many child, maternal and household factors were significantly associated with ITN usage across the two surveys. Specifically, children whose mothers had desirable health behaviours, from households with a good ITN supply, and living in the southern region had increased odds of using ITNs.
The increase in ITN usage observed in this study could probably be attributed to two reasons; First, the nationwide ITN distribution campaign in 2012, and a partial distribution campaign in early 2015, which were accompanied by awareness messages on the importance of using malaria interventions such as ITNs. In 2015, a higher proportion (32%) of the interviewed households reported that they sourced their ITNs from mass campaigns than any other sources . Second, the differences in survey periods (i.e. the 2015 survey was largely conducted during malaria transmission peak period (October–February) while most part of the 2010 survey was conducted outside the transmission peak period (June–November). Despite the observed increase in ITN usage, the Malawian ITN usage rate remains relatively lower than that in other countries in SSA such as Rwanda (75%) . The observed difference in ITN usage rates may be as a result of differences in ITN access rates at the time of the study with Rwanda reporting a relatively high ITN access of 64.2% compared to the 39% for Malawi . Additionally, the rates of households owning at least one ITN in Malawi have been fluctuating from 57% in 2010, 70% in 2014, and 57% in 2015 with high rates of ownership observed in the years soon after mass ITN campaigns . The results suggest the need for continued efforts in increasing household ITN ownership and access, through strengthened mass ITN distribution campaigns and routine distribution systems to vulnerable groups.
Children whose mothers were married, had desirable health behaviours, those from middle, rich and richest households, and from households with unimproved roofing were more likely to sleep in an ITN in 2010. Unmarried women may lack support from their spouses and may be disadvantaged in having access to resources . Previous research assessing the association between socio-economic status and net usage revealed conflicting results [5, 21,22,23]. Mothers from rich and middle-wealth households may have better access to information and resources that may help them reinforce the decision to have their children sleep under an ITN . Consistent with a previous study in Ethiopia, having improved roofing in a household may foster a false sense of protection from mosquitoes, and hence families may be more likely to forego nets . Women already practicing good health behaviours might be more receptive to other health-promotion practices, such as the use of ITNs . Ethnicity and geographical regions were highly correlated with cultural beliefs and social norms which may influence health behaviours . A higher malaria prevalence was reported in the southern region than the northern part of Malawi ; hence, people in the south may feel vulnerable to malaria, thereby making greater efforts to use intervention strategies already in place .
The diminishing influence of these aforementioned factors could be related to the mass ITN distribution campaign that was conducted in 2012, which also included a comprehensive awareness campaign. It further appears that the campaign achieved some moderate success in alleviating the influence of socio-economic factors on net usage, as well as in minimizing cultural and regional differences in net usage. This underscores the importance of mass campaigns in reducing disparities in ITN usage behaviour among various segments of the population in Malawi. Future mass campaigns should, therefore, not only emphasize ITN distribution, but also strengthen behavioural change communication messages related to ITN usage.
Additionally, data indicated that older children (≥ 24 months) were less likely to sleep in an ITN compared to those aged ≤ 12 months. It was shown that as children grow older, their access to ITN is lost to younger siblings . Moreover, younger children, especially those that are breastfeeding, are more likely to share a bed with their parents, thereby increasing their chances of sleeping under an ITN . Hence, there is a need to holistically enhance ITN usage among all age groups of children to achieve the malaria elimination goal in Malawi. Mother’s education remained a significant factor, consistent with previous research . A mother’s level of education may portray the level of autonomy the mother has on important issues such as health decisions . Autonomous women were associated with improved health behaviours [32, 33] which may subsequently affect the behaviour of their children .
Children from households headed by a female were associated with reduced odds of ITN usage. Households headed by a female may have limited access to resources , such as radios, newspapers and television to expose them to important health messages compared to households headed by a male, which may ultimately play a role in their health behaviours, including ITN usage for their younger ones. In addition, a male’s position on ITNs might influence household ITN usage as reported in Liberia . Similarly, rural residents might have poor access to health-related information and other resources [3, 25, 37], hence this explains the finding that children from rural areas being less likely to use ITN compared to urban residents. Moreover, households in rural areas might also face problems of limited public health resources and administrative support within the community.
ITN usage is largely dependent on access . This study demonstrated increased odds of ITN usage among children from households with good ITN supply compared to those with very poor ITN supply. Compared to smaller households, larger households face challenges in achieving desirable intra-household ITN supply . This finding underscores the need for malaria programmes to take into consideration family sizes during ITN distribution which may help increase intra-household ITN supply and, ultimately, help improve usage.
In 2015, those belonging to the Protestant religious group had reduced odds of using ITN compared to belonging to the Catholic religious group. This is consistent with a previous study in Ghana where Catholics were more likely to use ITNs compared to those who practiced traditionalism . Efforts to enhance ITN utilization should consider partnership with community religious institutions as an essential approach to scaling up ITN utilization by children.
There are several limitations to this study that should be noted. First, because of the limited number of variables in the MDHS, an array of other important factors related to ITN usage, particularly user-side factors, such as satisfaction with the nets or difficulties associated with using the nets, were not examined. However, this study captured many important child, maternal and household characteristics that could prove vital for effective ITN programmes. Second, the cross-sectional design limited the study from drawing causal inferences between explanatory factors and ITN usage. Third, the study used wealth quintiles which were calculated using PCA model and not multiple component analysis which has been shown to provide more accurate wealth index because of its ability to accommodate both continuous and dichotomous variables . The inability of PCA analysis to accommodate continuous variables makes it difficult to determine wealth quintile cut-off points where most households have the same assets which may result in allocating the same or very similar wealth scores . Finally, the question on ITN usage by children was asked from the mother which could be subject to social desirability bias as mothers may want to prove that they are taking good care of their children by making them sleep under ITNs. Despite these limitations, the study provides evidence of the importance of considering child, maternal and household characteristics, in both research and actual practice, to promote the use of ITNs.