Maternal responses to childhood febrile illnesses in an area of seasonal malaria transmission in rural Ethiopia

Although malaria is the leading cause of illness and death among children less than 5 years of age, there is limited information on mother's response and experience about diagnosis and treatment of the disease in children in rural areas of Ethiopia. The objective of this study was to assess maternal responses and treatment seeking behaviour for children reported to have malaria. A community-based cross-sectional study was conducted between October and November 2003 in Adami Tulu District, south-central Ethiopia. Mothers/caretakers of children less than 5 years of age were interviewed about history of febrile illness suspected to be malaria for all under-five children and the actions taken in the 2 weeks prior to the survey. Of 3872 children identified in 2372 households, 817 (21.1%) had febrile illness reported to be malaria according to the mothers/caretakers. The main symptoms included fever (99%), shivering/chills (92.2%), vomiting (55.1%), sleeplessness/restlessness (12.9%) and refusal to feed (21.3%). Of the total febrile children, 27.3% sought the first care from a public health facility, 27% visited community health workers (CHWs), 25.7% taken to private clinics, 6.4% received home treatment, and 13.3% did not get any care. Among 710 children who reported to receive any type of anti-malarial treatment, 78.8% got it from one source, 19.4% visited two sources and 1.8% sought three sources. Only 28% of the children received any form of treatment within 24h of the onset of illness. Public facilities, private clinics and CHWs were the main sources of care sought by febrile children. Strengthening peripheral health services and community-based interventions using CHWs at village levels would improve the early diagnosis and treatment of malaria among children.     

Risk of Plasmodium falciparum infection during a malaria epidemic in highland Kenya, 1997

Malaria epidemics in highland areas of East Africa have occurred with increasing frequency since the late 1980s, but the actual risk of Plasmodium falciparum infection in children and adults during these epidemics has not been well characterized. During a malaria epidemic in a highland area of Kenya, risk of infection was assessed in 50 adults (> or =18 years old) and 32 children (< or =8 years old) after treatment and parasitologic clearance with sulfadoxine-pyrimethamine treatment. Over a 10-week period, 36 of the 82 study participants (43.9%) became infected. The risk of infection was similar in children and adults (hazard ratio for children = 1.21, 95% CI: 0.63-2.33). These findings contrast with the age-related protection from infection reported in areas of stable, intense transmission, and demonstrate that during malaria epidemics, both children and adults in highland areas of Kenya are at high risk of infection.     

Epidemiology of malaria in the Papua New Guinean highlands

Objectives To conduct an in‐depth investigation of the epidemiology of malaria in the Papua New Guinea (PNG) highlands and provide a basis for evidence‐based planning and monitoring of intensified malaria control activities. Methods Between December 2000 and July 2005, 153 household‐based, rapid malaria population surveys were conducted in 112 villages throughout the central PNG highlands. The presence of malaria infections was determined by light microscopy and risk factors assessed using a structured questionnaire. The combined dataset from all individually published surveys was reanalysed. Results The prevalence of malaria infections in the different surveys ranged from 0.0% to 41.8% (median 4.3%) in non‐epidemic surveys and 6.6% to 63.2% (median 21.2%, P < 0.001) during epidemics. Plasmodium falciparum was the predominant infection below 1400 m and during epidemics, Plasmodium vivax at altitudes >1600 m. Outside epidemics, prevalence decreased significantly with altitude, was reduced in people using bed nets [odds ratio (OR) = 0.8, P < 0.001] but increased in those sleeping in garden houses (OR = 1.34, P < 0.001) and travelling to highly endemic lowlands (OR = 1.80, P < 0.001). Below 1400 m, malaria was a significant source of febrile illness. At higher altitudes, malaria was only a significant source of febrile illness during epidemic outbreaks, but asymptomatic malaria infections were common in non‐epidemic times. Conclusions Malaria is once again endemic throughout the PNG highlands in areas below 1400–1500 m of altitude with a significant risk of seasonal malaria outbreaks in most area between 1400–1650 m. Ongoing control efforts are likely to result in a substantial reduction in malaria transmission and may even result in local elimination of malaria in higher lying areas.     

Economic impact of febrile morbidity and use of permethrin-impregnated bed-nets in a malarious area I. Study of demographics, morbidity, and household expenditures associated with febrile morbidity in the Republic of Benin

In preparation for a study on the effect of bed net use on malaria, this article describes febrile morbidity and malaria expenditures in a sub-Saharan area (Benin) of hyperendemic malaria. The 325 randomly selected households were visited weekly between April 1994 and March 1995 to determine febrile morbidity and household expenditures for prevention and treatment. The results indicate that rural children had two febrile episodes annually compared with 0.3 episodes among children living in the city. There was no difference in mean annual febrile episodes between adults and children (adults = 1.5, children = 1.5; P = 0.48) and in the expenditures per febrile episode (adults = US$1.85, children = US$1.62; P = 0.45). Annual prevention expenditures were higher for adults than for children (US$1.73 and US$1.28, respectively; P < 0.001), although there was no significant difference in expenditures for annual treatment for adults and children (US$2.15 and US$2.34, respectively). These and other findings are analyzed further and discussed.     

Spatial and temporal variations of malaria epidemic risk in Ethiopia: factors involved and implications

The aim of this study was to describe spatial and temporal variations in malaria epidemic risk in Ethiopia and to examine factors involved in relation to their implications for early warning and interpretation of geographical risk models. Forty-eight epidemic episodes were identified in various areas between September 1986 and August 1993 and factors that might have led to the events investigated using health facility records and weather data. The study showed that epidemics in specific years were associated with specific geographical areas. A major epidemic in 1988 affected the highlands whereas epidemics in 1991 and 1992 affected highland-fringe areas on the escarpments of the Rift Valley and in southern and north-western parts of the country. Malaria epidemics were significantly more often preceded by a month of abnormally high minimum temperature in the preceding 3 months than based on random chance, whereas frequency of abnormally low minimum temperature prior to epidemics was significantly lower than expected. Abnormal increases of maximum temperature and rainfall had no positive association with the epidemics. A period of low incidence during previous transmission seasons might have aggravated the events, possibly due to low level of immunity in affected populations. Epidemic risk is a dynamic phenomenon with changing geographic pattern based on temporal variations in determinant factors including weather and other eco-epidemiological characteristics of areas at risk. Epidemic early warning systems should take account of non-uniform effects of these factors by space and time and thus temporal dimensions need to be considered in spatial models of epidemic risks.     

Can Long-lasting Insecticide-treated Bednets with Holes Protect Children from Malaria?

Although long-lasting insecticide-treated bednets (LLINs) have been widely used for malaria control, little is known about how the condition of LLINs affects the risk of malaria infection. The objective of this cross-sectional study was to examine the association between the use of LLINs with holes and caregiver-reported malaria diagnosed in children under five years of age (U5). Data were collected in Boboye health district, Niger, in 2010. Surveyors conducted interviews and bednet inspections in 1,034 households. If a household had a U5 child, the surveyor asked the caregiver whether the child had experienced a fever episode in the past two weeks that entailed standard treatment for uncomplicated malaria at a healthcare facility. The authors analyzed the association between the use of LLINs with holes and caregiver-reported malaria episodes in U5 children using logistic regression, adjusted for possible confounders. Of the 1,165 children included in the analysis, approximately half (53.3%) used an intact LLIN while far fewer (10.6%) used a LLIN with holes. Compared to children using an intact LLIN, children using a LLIN with holes were significantly more likely to have a caregiver-reported malaria episode (8.7% vs. 17.1%; odds ratio: 2.23; 95% confidence interval: 1.24–4.01). In this study site, LLINs with holes were less protective than intact LLINs.     

Epidemic malaria in the highlands of Papua New Guinea

As part of a larger study into the epidemiology of malaria in the highlands of Papua New Guinea, outbreak investigations were carried out at the end of the 2002 rainy season in 11 villages situated between 1,400 and 1,700 meters above sea level that had reported epidemics. Locations and timing of these epidemics corresponded largely to those reported in the pre-control era of the 1960s and 1970s. On average, 28.8% (range = 10.3-63.2%) of people in each of the 11 villages were found to be infected with malaria. Plasmodium falciparum accounted for 59% of all identified infections and P. vivax for 34%. The majority (53%) of infections were symptomatic. Although symptomatic infections were most common in children 2-9 years of age (36%), even in adults a prevalence of 20% was observed. A comparison with earlier non-epidemic data in three of the villages without easy access to health care showed markedly increased levels of morbidity, with 6-10-fold increases in parasite prevalence, a 3-fold increase in both measured and reported fevers, and a 12-fold increase in enlarged spleens. The average hemoglobin levels were reduced by 2.3-3.5 g/dL, with a concurrent increase in moderate to severe anemia (hemoglobin level < 7.5 g/dL) from 0.0-3.3% to 3.8-18.4%. These massive increases in morbidity have devastating impact on the affected communities and highlight that malaria epidemics are a serious and increasing public health problem in the highlands of Papua New Guinea.     

Equity and seeking treatment for young children with fever in Nigeria: a cross-sectional study in Cross River and Bauchi States

Background

Poor children have a higher risk of contracting malaria and may be less likely to receive effective treatment. Malaria is an important cause of morbidity and mortality in Nigerian children and many cases of childhood fever are due to malaria. This study examined socioeconomic factors related to taking children with fever for treatment in formal health facilities.

Methods

A household survey conducted in Bauchi and Cross River states of Nigeria asked parents where they sought treatment for their children aged 0–47 months with severe fever in the last month and collected information about household socio-economic status. Fieldworkers also recorded whether there was a health facility in the community. We used treatment of severe fever in a health facility to indicate likely effective treatment for malaria. Multivariate analysis in each state examined associations with treatment of childhood fever in a health facility.

Results

43% weighted (%wt) of 10,862 children had severe fever in the last month in Cross River, and 45%wt of 11,053 children in Bauchi. Of these, less than half (31%wt Cross River, 44%wt Bauchi) were taken to a formal health facility for treatment. Children were more likely to be taken to a health facility if there was one in the community (OR 2.31 [95% CI 1.57–3.39] in Cross River, OR 1.33 [95% CI 1.0–1.7] in Bauchi). Children with fever lasting less than five days were less likely to be taken for treatment than those with more prolonged fever, regardless of whether there was such a facility in their community. Educated mothers were more likely to take children with fever to a formal health facility. In communities with a health facility in Cross River, children from less-poor households were more likely to go to the facility (OR 1.30; 95% CI 1.07-1.58).

Conclusion

There is inequity of access to effective malaria treatment for children with fever in the two states, even when there is a formal health facility in the community. Understanding the details of inequity of access in the two states could help the state governments to plan interventions to increase access equitably. Increasing geographic access to health facilities is needed but will not be enough.

Electronic supplementary material

The online version of this article (doi:10.1186/2049-9957-4-1) contains supplementary material, which is available to authorized users.     

Factors influencing adherence to referral advice following pre-referral treatment with artesunate suppositories in children in rural Tanzania

Objective WHO recommends artemisinin suppository formulations as pre‐referral treatment for children who are unable to take oral medication and cannot rapidly reach a facility for parenteral treatment. We investigated factors influencing caretakers’ adherence to referral advice following pre‐referral treatment of their children with rectal artesunate suppositories. Methods The study was nested within an intervention study that involved pre‐referral treatment of all children who came to a community dispenser for treatment because they were unable to take oral medications because of repeated vomiting, lethargy, convulsions or altered consciousness. All patients who did not comply with referral advice were stratified by actions taken post‐referral: taking their children to a drug shop, a traditional healer, or not seeking further treatment, and added to a random selection of patients who complied with referral advice. Caretakers of the children were interviewed about their socio‐economic status (SES), knowledge about malaria, referral advice given and actions they took following pre‐referral treatment. Interview data for 587 caretakers were matched with symptoms of the children, the time of treatment, arrival at a health facility or other actions taken post–pre‐referral treatment. Results The majority (93.5%) of caretakers reported being given referral advice by the community drug dispenser. The odds of adherence with this advice were three times greater for children with altered consciousness and/or convulsions than for children with other symptoms [odds ratio (OR) 3.47, 95% confidence interval (CI) 2.32–5.17, P < 0.001]. When questioned, caretakers who remembered when (OR 2.19, 95% CI 1.48–3.23, P < 0.001) and why (OR 1.77, 95% CI 1.07–2.95, P = 0.026) they were advised to proceed to health facility – were more likely to follow referral advice. Cost did not influence adherence except within a catchment area of facilities that charged for services. In these areas, costs deterred adherence by four to five times for those who had previously paid for laboratory services (OR = 0.25, 95% CI: 0.09–0.67, P = 0.006) or consultation (OR 0.20, 95% CI: 0.06–0.61, P = 0.005) compared with those who had not. Conclusion When given referral advice, caretakers of patients with life‐threatening symptoms adhere to referral advice more readily than other caretakers. Health service charges deter adherence.     

Malaria morbidity among school children living in two areas of contrasting transmission in western Kenya

Research in malaria-endemic areas is usually focused on malaria during early childhood. Less is known about malaria among older school age children. The incidence of clinical attacks of malaria was monitored, using active case detection in primary schools, in two areas of western Kenya that differ in the intensity of transmission. Clinical malaria was more common in schools in the Nandi highlands, with a six-fold higher incidence of malaria attacks during the malaria epidemic in 2002, compared with school children living in a holoendemic area with intense perennial transmission during the same period. The high incidence coupled with the high parasite densities among cases is compatible with a low level of protective immunity in the highlands. The malaria incidence among school children exposed to intense year-round transmission (26 per 100 school children per year) was consistent with reports from other holoendemic areas. Taken together with other published studies, the data suggest that malaria morbidity among school age children increases as transmission intensity decreases. The implications for malaria control are discussed.     

Adherence to artesunate–amodiaquine combination therapy for uncomplicated malaria in children in Zanzibar, Tanzania

Objectives  To estimate caretaker adherence to co-blistered, but not co-formulated, artesunate-amodiaquine (AsAq) for uncomplicated malaria and identify factors associated with caretaker adherence.
Methods  Cross sectional household survey of caretakers of 210 children under 5 years of age who had been prescribed and dispensed AsAq at 21 public health facilities (HFs). The caretakers were interviewed in their homes on the 4th day of receiving the 3 day treatment. Adherence of caretakers was assessed by self report and pill count.
Results  Caretaker adherence to AsAq was 77% (95% CI: 67%–87%). Non-adherence resulted in under-dosing ¾ of the time and was most often in the form of wrong daily doses due to misunderstanding or forgetting the correct dose regimens. Predictors of adherence were education exceeding 7 years (OR = 5.08, P  = 0.008) and receiving the exact number of pills to complete the treatment regimen (OR = 4.09, P  = 0.006). All caretakers of children who were administered the first dose at the HF had adhered to the treatment.
Conclusion  We found moderate levels of caretaker adherence to AsAq. Further improvement could be achieved by producing dose-specific packaging for infants, providing clear instructions and giving the first dose under observation at the HF.     

High Levels of Asymptomatic and Subpatent Plasmodium falciparum Parasite Carriage at Health Facilities in an Area of Heterogeneous Malaria Transmission Intensity in the Kenyan Highlands

In endemic settings, health facility surveys provide a convenient approach to estimating malaria transmission intensity. Typically, testing for malaria at facilities is performed on symptomatic attendees, but asymptomatic infections comprise a considerable proportion of the parasite reservoir. We sampled individuals attending five health facilities in the western Kenyan highlands. Malaria prevalence by rapid diagnostic test (RDT) was 8.6–32.9% in the health facilities. Of all polymerase chain reaction-positive participants, 46.4% (95% confidence interval [95% CI] = 42.6–50.2%) of participants had infections that were RDT-negative and asymptomatic, and 55.9% of those infections consisted of multiple parasite clones as assessed by merozoite surface protein-2 genotyping. Subpatent infections were more common in individuals reporting the use of non-artemisinin–based antimalarials in the 2 weeks preceding the survey (odds ratio = 2.49, 95% CI = 1.04–5.92) compared with individuals not reporting previous use of antimalarials. We observed a large and genetically complex pool of subpatent parasitemia in the Kenya highlands that must be considered in malaria interventions.     

Impact of the malaria control campaign (1993-1998) in the highlands of Madagascar: parasitological and entomological data

Malaria transmission in the central highlands of Madagascar was interrupted in the 1960s by a national control program that used DDT indoor spraying and mass treatment with chloroquine. At the end of the 1980s in this region, epidemic malaria reappeared. Italian health authorities provided technical assistance to the National Malaria Control Program since the beginning of the resurgence of malaria in the central highlands. Yearly residual house spraying performed for 5 years (1993-1998) and the availability of antimalarial drugs reduced malaria transmission to very low levels, with improvement in parasitologic and entomologic indexes. A significant reduction of malaria prevalence was observed in the villages located at altitudes of 1,000-1,500 m, corresponding to the stratum of unstable malaria that was the main target of the antivector interventions. A significant reduction of malaria prevalence was also observed in the villages located at altitudes of 900-1,000 m, where malaria transmission is stable. The main vector Anopheles funestus was dramatically reduced in abundance and distribution in the sprayed areas.     

Association between climate variability and malaria epidemics in the East African highlands

The causes of the recent reemergence of Plasmodium falciparum epidemic malaria in the East African highlands are controversial. Regional climate changes have been invoked as a major factor; however, assessing the impact of climate in malaria resurgence is difficult due to high spatial and temporal climate variability and the lack of long-term data series on malaria cases from different sites. Climate variability, defined as short-term fluctuations around the mean climate state, may be epidemiologically more relevant than mean temperature change, but its effects on malaria epidemics have not been rigorously examined. Here we used nonlinear mixed-regression model to investigate the association between autoregression (number of malaria outpatients during the previous time period), seasonality and climate variability, and the number of monthly malaria outpatients of the past 10-20 years in seven highland sites in East Africa. The model explained 65-81% of the variance in the number of monthly malaria outpatients. Nonlinear and synergistic effects of temperature and rainfall on the number of malaria outpatients were found in all seven sites. The net variance in the number of monthly malaria outpatients caused by autoregression and seasonality varied among sites and ranged from 18 to 63% (mean=38.6%), whereas 12-63% (mean=36.1%) of variance is attributed to climate variability. Our results suggest that there was a high spatial variation in the sensitivity of malaria outpatient number to climate fluctuations in the highlands, and that climate variability played an important role in initiating malaria epidemics in the East African highlands.     

Local fever illness classifications: implications for home management of malaria strategies

BACKGROUND: The Ugandan Ministry of Health has adopted the WHO Home Based Fever Management strategy (HBM) to improve access to antimalarial drugs for prompt (<24 h) presumptive treatment of all fevers in children under 5 years. Village volunteers will distribute pre-packed antimalarials free of charge to caretakers of febrile children 2 months to 5 years ('Homapaks'). OBJECTIVE: To explore the local understanding and treatment practices for childhood fever illnesses and discuss implications for the HBM strategy. METHODS: Focus Group Discussions were held with child caretakers in three rural communities in Kasese district, West Uganda, and analysed for content in respect to local illness classifications and associated treatments for childhood fevers. RESULTS: Local understanding of fever illnesses and associated treatments was complex. Some fever illness classifications were more commonly mentioned, including 'Fever of Mosquito', 'Chest Problem', 'the Disease', 'Stomach Wounds' and 'Jerks', all of which could be biomedical malaria. Although caretakers refer to all these classifications as 'fever' treatment differed; some were seen as requiring urgent professional western treatment and others were considered severe but 'non-western' and would preferentially be treated with traditional remedies. CONCLUSIONS: The HBM strategy does not address local community understanding of 'fever' and its influence on treatment. While HBM improves drug access, Homapaks are likely to be used for only those fevers where 'western' treatment is perceived appropriate, implying continued delayed and under-treatment of potential malaria. Hence, HBM strategies also need to address local perceptions of febrile illness and adapt information and training material accordingly.     

Malaria in Uganda: challenges to control on the long road to elimination: I. Epidemiology and current control efforts

Malaria remains one of the leading health problems of the developing world, and Uganda bears a particularly large burden from the disease. Our understanding is limited by a lack of reliable data, but it is clear that the prevalence of malaria infection, incidence of disease, and mortality from severe malaria all remain very high. Uganda has made progress in implementing key malaria control measures, in particular distribution of insecticide-impregnated bednets, indoor residual spraying of insecticides, utilization of artemisinin-based combination therapy to treat uncomplicated malaria, and provision of intermittent preventive therapy for pregnant women. However, despite enthusiasm regarding the potential for the elimination of malaria in other areas, there is no convincing evidence that the burden of malaria has decreased in Uganda in recent years. Major challenges to malaria control in Uganda include very high malaria transmission intensity, inadequate health care resources, a weak health system, inadequate understanding of malaria epidemiology and the impact of control interventions, increasing resistance of parasites to drugs and of mosquitoes to insecticides, inappropriate case management, inadequate utilization of drugs to prevent malaria, and inadequate epidemic preparedness and response. Despite these challenges, prospects for the control of malaria have improved, and with attention to underlying challenges, progress toward the control of malaria in Uganda can be expected.     

Plasmodium infection,anaemia and mosquito net use among school children across different settings in Kenya

Objective To investigate risk factors, including reported net use, for Plasmodium infection and anaemia among school children and to explore variations in effects across different malaria ecologies occurring in Kenya. Methods This study analysed data for 49 975 school children in 480 schools surveyed during a national school malaria survey, 2008–2010. Mixed effects logistic regression was used to investigate factors associated with Plasmodium infection and anaemia within different malaria transmission zones. Results Insecticide‐treated net (ITN) use was associated with reduction in the odds of Plasmodium infection in coastal and western highlands epidemic zones and among boys in the lakeside high transmission zone. Other risk factors for Plasmodium infection and for anaemia also varied by zone. Plasmodium infection was negatively associated with increasing socio‐economic status in all transmission settings, except in the semi‐arid north‐east zone. Plasmodium infection was a risk factor for anaemia in lakeside high transmission, western highlands epidemic and central low‐risk zones, whereas ITN use was only associated with lower levels of anaemia in coastal and central zones and among boys in the lakeside high transmission zone. Conclusions The risk factors for Plasmodium infection and anaemia, including the protective associations with ITN use, vary according to malaria transmission settings in Kenya, and future efforts to control malaria and anaemia should take into account such heterogeneities among school children.     

Indirect Protection from Vaccinating Children against Influenza A Virus Infection in Households

Influenza vaccination is an important intervention to prevent influenza virus infection. Our previous analysis suggested that indirect protection is limited in an influenza B epidemic in Hong Kong. We further analyzed six influenza A epidemics to determine such potential. We applied a statistical model to estimate household transmission dynamics in the 3 influenza A(H3N2) and 3 pandemic influenza A(H1N1) epidemics. Then, we estimated the reduction in infection risk among unvaccinated household members when all children in households are vaccinated, with different assumptions on vaccine efficacy (VE). In the optimal scenario that VE was 70%, the reduction to the total probability of infection was only marginal, with relative probabilities ranged from 0.91–0.94 when all children in households were vaccinated because community was by far the main source of infection during the six epidemics in our study. The proportion of cases attributed to household transmission was 10% (95% CrI: 7%, 13%). Individual influenza vaccination is important even when other household members are vaccinated, given the degree of indirect protection is small.