In the years 2005 through 2008, Zambia systematically tracked malaria control program success in terms of attracting and using growing financial resources; increasing procurement and distribution of key commodities to homes and health facilities; increasing national coverage of interventions (particularly the prevention interventions of ITNs, IRS, and IPTp); reducing infection and illness; improving post-neonatal infant and child survival; and achieving equity of service delivery with concomitant disease reduction among the poorest and rural populations.
The documented progress is remarkable and to be celebrated by the country and those who contributed importantly in the work. The findings are consistent with what is known about the efficacy of the individual interventions.24–28
The documented reduction in all-cause child mortality (29% overall and ~37% in the post-neonatal infant and child periods) is substantial and perhaps larger than would be anticipated on the basis of malaria control alone. Although we looked for other disease prevention and control work that might be important contributing factors, none were readily apparent. Of note, although there was no change in childhood stunting and wasting, there was a 48% reduction in underweight children and this may have been due both to less repeated malaria infections and other factors of nutrient intake. There was an increase in the proportion of children with exclusive breast feeding in the first 6 months of life but this was coupled with a reduction in the proportion of children with continued breast feeding after 20 months of age. The rapid success seen in Zambia may be explained by the country's broadly semi-immune population which, when quickly covered with highly effective interventions that markedly decrease malaria transmission intensity, will show dramatic improvements within one malaria transmission season.
The consistency of the findings across the spectrum of receiving funding, documenting procurement and distribution of malaria prevention commodities, achieving high and equitable coverage, and showing national data on reduced morbidity and mortality makes a compelling story that malaria control is working. At the local level in communities and health facilities, the story is similar. The introduction of systems to record malaria outpatient cases, inpatient cases, and malaria deaths, with the presence of stable diagnostic capacity, have documented decreasing slide positivity rates in several facilities where reporting has been consistent and where interventions have been introduced.21
Similarly, the routine health information systems in districts where stable reporting has been maintained over time are showing substantial declines in both malaria infections and cases in malaria deaths.29
Thus, the national survey data and the local HMIS data are showing consistent progress in recent years.
Efforts in Zambia from 2005 through 2008 focused on scaling up malaria prevention services (ITNs and IRS for households, IPTp and ITNs for pregnant women), whereas curative services emphasized provision of improved diagnostics and quality of care for those attending facilities for malaria episodes.30
Despite being an early adopter of artemisinin-based combination therapy for treatment of malarial episodes,31
access to health care treatment services, especially in rural areas, remains challenging because of insufficient human resources for health32
and the difficulties in increasing quality care for febrile episodes.11,13
The Government of Zambia took bold steps to address universal access to health care by removing user fees in 2006 for rural areas,33
but many challenges remain to adequately address staffing requirements to meet established plans. More recently, the National Malaria Control Program embarked on an ambitious plan to train community health workers in malaria testing and treatment in response to calls for expanding access to treatment services.34,35
The nation of Zambia and its donor partners have invested extensively in malaria control and would undoubtedly like to see socio-economic progress along with the documented disease burden reduction. Although not a fully national effort, a recent review of data in the copper mining and sugar industries where company-supported malaria control efforts in the workforce and in the surrounding communities showed that this investment is improving production and is cost saving. Industry-collected data between 2001 and 2007 show that their investment in prevention has led to marked reduction in malaria cases in their workforce and families and improved work attendance, production-per-worker, and overall production for the plants. The data from 2006 accounting for money spent on malaria prevention and treatment and money recouped from fewer cases, fewer lost work hours and better production showed that Mopani Copper Mines saved US$295,718 and Zambia Sugar PLC saved US$550,379—saving approximately two dollars for every dollar invested in malaria prevention.36
Although it will take some time to assess links between malaria control and fully national economic benefits, the results of these industry studies are quite encouraging.
In the context of implementing a national program, there is no comparison population, other than historical, so this report can only be descriptive. However, information presented is from standard documented sources (DHS and MIS surveys, administrative and HMIS data, and industry case studies conducted with support from academic institutions) and the sum of these provides a broad consistency to the findings. This preliminary assessment of the dramatic drop in child mortality rates will be augmented by future national mortality studies allowing further exploration and analysis over time. The mortality data collected is “all-cause mortality” and not disease specific; thus, the further analysis will have limited ability to directly explore the contribution of malaria control to malaria-specific mortality decline. In addition, the DHS measures child mortality in the interval up to 5 years before the survey (e.g., 2007 survey measures mortality from 2003 through 2007), however this likely includes changes that might have occurred related to the scale up of malaria control interventions in the 2005–2007 interval. Although theoretically one could examine mortality rates in the 2003–2004 interval and compare them with the 2005–2007 interval, the DHS sample size precludes statistically relevant comparisons for these sub-analyses. Recognizing these limitations, the initial review of the DHS survey data in 2001/2 and 2007 suggests that the largest change in disease control has been the rapid scale up of malaria interventions and this likely has contributed importantly to the overall improved child survival.
Zambia is now moving toward completing the final steps for achieving and sustaining high national coverage rates of malaria control interventions to further reduce the remaining morbidity, mortality, and transmission. Much of the success in reducing illness and death has already been achieved and one can anticipate that further declines in illness and death rates will be only modest in comparison to what has already been achieved. Thus, future success will be seen in holding morbidity and mortality at these new low levels and any future improvements will need to be compared with the pre-scale-up mortality estimates from the DHS 2001/2. As Zambia expands program work to further reduce malaria transmission, the program will need to consider specific measures of transmission that can be tracked over time to understand success in the future.