This study aimed to investigate and identify factors that influence recurrence of malaria in a severe form in selected primary healthcare centres in South Sudan. The finding of the study hence would contribute to the understanding of factors limiting the achievement of the malaria control and elimination programme objectives in South Sudan. The finding of this study showed that a good proportion of the population had access to insecticide treated net and other environmental preventive measures. This suggested the population in the study area might have benefitted from the investment made towards improving access to proven preventive measures for malaria, especially the treated mosquito nets. Previous studies have shown that access to an effective utilization of treated mosquito net significantly prevents the occurrence of both uncomplicated malaria (8,,22,23), and complicated malaria (14).
The finding of this study also showed prevalence of severe recurrent malaria among the participants to be higher in the five years old and above population when compared to the under-five years old population. This is in consistency with previous studies; however, more sub-classifications of age were applied in those studies (14,23,32). Further investigation on this may be suggested, in line with the WHO request for continuous monitoring of drug efficacy (33,34), as the possibility of gradual emergence of drug resistance malaria infection may not be ruled out, and this may undermine the malaria control efforts. According to WHO, in areas of moderate or intense malaria transmission, partial immunity is developed over years of exposure especially among adults; and while it never provides complete protection, it does reduce the risk that malaria infection will cause severe diseases (33,34). Notwithstanding, It is important to conduct further investigation to detect if the prevalence of severe recurrent malaria among adult participants was as a result of waned immunity (being an area of malaria endemicity), or a factor of drug resistance or otherwise.
One major finding this study revealed was that among those who did not complete their treatment, 76.7% had severe recurrent malaria, unlike 35.1% seen among those who completed their treatment. While there is dearth of data on recurrence of severe malaria, previous study has shown 24.1% recurrence of malaria at least one episode within 180 days of treatment completion and were attributed to treatment failure (35). Other studies showed 0-13.5% malaria recurrence following treatment with standard regimen (36,37,38). The finding of this study further revealed that ‘completion or not’ of prescribed standard malaria treatment regimen by patient was a significant factor to the severity of malaria recurrence among the population. The finding showed significant association irrespective of the employment, marital, nutritional, or preventive measure access status of the participants. Previous malaria studies have shown non-completion of treatment to be a predisposing factor of severe recurrent malaria (14,39). The government through the ministry of health and various partners have been investing enormous resources in the prevention and control of malaria including increasing access to treatment. Further studies to investigate the types of anti-malaria treatment given, whether treatment is completed or not by the patient, and factors influencing adherence to anti-malaria treatment in post-conflict settings like the South Sudan’s population is highly recommended. Meanwhile, it is necessary for clinicians and health stakeholders to create methods and/or strategies that will ensure patients take and complete medications accordingly as prescribed, on time, including patient follow-up.
Our study also revealed that severity of recurrent malaria had a significant relationship with marital status. Married participants were less likely to have severe recurrent malaria when compared with those who were single. The finding might have resulted from the fact that married persons could lend more care and protection to one another at home including preventive and prevention of health care such as providing reminders on medication, providing support in the proper utilization of treated mosquito nets among others, unlike single persons. Most of the previous studies that examined the social determinants of malaria did not evaluate the relationship between severe malaria or recurrent severe malaria and marital status. However, similar to the finding reported in this study for the factor of marital status, previous studies found significant relationship between age, gender, and occurrence of severe malaria (26).
The severity of malaria recurrence was also more likely among those who are not employed when compared with those gainfully employed. The possibility of reduced positive emotional state of mind might have affected the health seeking behaviour of the unemployed population. Furthermore, the finding of the study showed significant association between participants who ate at most once or twice daily had severe recurrent malaria compared with those who ate a minimum of thrice meal daily. This can be argued that participants with access to more or adequate meals should have better health status to prevent and /or respond to illness. This does not contradict the fact that there could be a possibility that those who had access to more meals might not have had access to a balanced or quality diet, hence limited benefit to their body health systems; and therefore could have reduced the protective effect against the severity of recurrent malaria in our study (adjOR=9.03, 95% CI: 4.52-18.00, p<0.001) . This study should have but could not further investigate the type and quality of meal the participants had; hence, it will be beneficial to the government of South Sudan if further studies can explore the type and effect of meal quality on the recurrence of severe malaria. The findings of various studies conducted suggested poor feeding as a result of poverty to be a factor influencing malaria occurrence (40,41,42). Available evidence alluded to the fact that where malaria thrives most, human societies have prospered least, and this suggests that malaria and poverty are closely linked (43,44). Programmes which focus on sustainable empowerment of families and communities economically may contribute to reducing the incidence of recurrent severe malaria and should be more advocated in the area and other areas with similar epidemiological patterns for severe malaria.
The findings of this study conversely showed that participants who had at least one malaria preventive measure developed severe malaria compared with those who had no prevention. Those with at least one preventive measure were more 3.8 times as likely to have severe recurrent malaria compared with those who had no prevention measure. Factors responsible for this finding should be investigated. There is a likelihood of poor compliance to effective utilization of these preventive measures. Furthermore, the chance of false protection might have existed among the population, hence increasing their exposure to having recurrent severe malaria. It will be useful to investigate further the type and quantity of preventive measures the population had access to and how effectively they comply with the use of these measures. The findings from previous studies showed that attitude and inadequate knowledge of the effective use of malaria preventive and control measures affect compliance and the outcome (14,22,23,24,25). Among available preventive measures, WHO recommends protection for all people at risk of malaria with effective malaria vector control – insecticide-treated mosquito nets and indoor residual spraying which are effective in a wide range of circumstances (33).
Study limitation
Findings of our study must be considered in view of its limitations. Firstly, the use of patient-provided clinical data may have exposed the study to recall bias. However, considering that data was collected without specific attention drawn to our research question, we believe this bias to be minimal. Further, our retrospective use of the data implied that the spectrum of covariates that could be controlled in this study were limited. Within the available data, we made the best use of the available data to determine our final estimates. Lastly, we acknowledge that the use of antigen Plasmodium lactate dehydrogenase- RDT instead of the gold-standard microscopy blood film malaria test may have resulted in a number of false positive recurrent malaria cases in the study as past studies has proven that these RDTs can still detect antigen Plasmodium lactate dehydrogenase in the blood plasma as positive 28 (18–35) days after an antimalarial treatment. Although, this depends on the age and type of anti-malaria treatment received (45).