Search

Recent outbreaks of locally acquired mosquito-transmitted malaria in the United States demonstrate the continued risk for reintroduction of the disease. Since 1957, when CDC's Malaria Branch started conducting malaria surveillance, 63 outbreaks have occurred, constituting 156 cases (annual range: 1-32) that were a result of locally acquired mosquitoborne transmission. This report describes the steps that should be taken to 1) investigate a case that might have been acquired locally, 2) prevent a small focus of malaria cases from becoming a source of sustained transmission, and 3) inform clinicians regarding the process of an investigation so they can effectively address concerns and questions from patients.Although these locally acquired mosquito-transmitted outbreaks frequently involve only a limited number of infected persons, they frequently raise concerns in the community and require substantial public health resources. For example, as a result of the most recent local outbreak of eight malaria cases in Florida in 2003, reverse 911 telephone calls (a community notification system) were made to approximately 300,000 residents; insect repellent, postcards, flyers, and posters in multiple languages were distributed; public announcements were made through the media and to schools and homeless shelters; and notifications were sent to local hospitals and physicians to inform residents of that community.When a local health department investigates a potential locally acquired mosquito-transmitted case, the systematic inquiry should include epidemiologic, environmental, and laboratory components. Local and state health departments inquiring about the proper approach to investigate and control a potential locally acquired case frequently request urgent assistance and tools from CDC. This report provides a starting point for such investigations to local and state health departments by providing them with the tools necessary to initiate an investigation. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria in humans is caused by any of four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). These parasites are transmitted by the bite of an infective female Anopheles sp. mosquito. The majority of malaria infections in the United States occur among persons who have traveled to areas with ongoing malaria transmission. In the United States, cases can occur through exposure to infected blood products, congenital transmission, or local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers.Period Covered: This report summarizes cases in persons with onset of illness in 2004 and summarizes trends during previous years.Description of System: Malaria cases confirmed by blood film are mandated to be reported to local and state health departments by health-care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report.Results: CDC received reports of 1,324 cases of malaria, including four fatal cases, with an onset of symptoms in 2004 among persons in the United States or one of its territories. This number represents an increase of 3.6% from the 1,278 cases reported for 2003. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 49.6%, 23.8%, 3.6%, and 2.0% of cases, respectively. Seventeen patients (1.3% of total) were infected by two or more species. The infecting species was unreported or undetermined in 262 (19.8%) cases. Compared with 2003, the number of reported malaria cases acquired in the Americas (n = 173) increased 17.7%, whereas the number of cases acquired in Asia (n = 172) and Africa (n = 809) decreased 2.8% and 3.7%, respectively. Of 775 U.S. civilians who acquired malaria abroad, only 160 (20.6%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Four patients became infected in the United States; three cases were attributed to congenital transmission and one to laboratory-related mosquitoborne transmission. Four deaths were attributed to malaria, including two caused by P. falciparum, one by P. vivax, and one by a mixed infection with P. falciparum and P. malariae.Interpretation: The 3.6% increase in malaria cases in 2004, compared with 2003, resulted primarily from an increase in the number of cases acquired in the Americas but was offset by a decrease in the number of cases acquired in Africa and Asia. This limited increase might reflect local changes in disease transmission, increased travel to regions in which malaria is endemic, or fluctuations in reporting to state and local health departments. These changes likely reflect expected variation in annual reporting and should not be interpreted as indicating a longer-term trend. In the majority of reported cases, U.S. civilians who acquired infection abroad had not adhered to a chemoprophylaxis regimen that was appropriate for the country in which they acquired malaria.Public Health Actions: Additional investigations were conducted for the four fatal cases and four infections acquired in the United States. Persons traveling to a malarious area should take one of the recommended chemoprophylaxis regimens appropriate for the region of travel and use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently has a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should include a blood-film test for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning malaria prevention can be obtained from CDC at http://www.cdc.gov/travel or by calling the Malaria Hotline at telephone 770-488-7788. Recommendations concerning malaria treatment can be obtained at http://www.cdc.gov/malaria/diagnosis_treatment/treatment or by calling the Malaria Hotline. [ABSTRACT FROM AUTHOR]

Problem/Condition: Malaria in humans is caused by any of four species of intraerythrocytic protozoa of the genus Plasmodium (i.e., P. falciparum, P. vivax, P. ovale, or P. malariae). These parasites are transmitted by the bite of an infective female Anopheles sp. mosquito. The majority of malaria infections in the United States occur among persons who have traveled to areas with ongoing transmission. In the United States, cases can also occur through exposure to infected blood products, by congenital transmission, or by local mosquitoborne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travelers.Period Covered: This report covers cases with onset of illness in 2003, and summarizes trends over previous years.Description of System: Malaria cases confirmed by blood film are mandated to be reported to local and state health departments by health-care providers or laboratory staff. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS). Data from NMSS serve as the basis for this report.Results: CDC received reports of 1,278 cases of malaria with an onset of symptoms in 2003, including seven fatal cases, among persons in the United States or one of its territories. This number represents a decrease of 4.4% from the 1,337 cases reported for 2002. P. falciparum, P. vivax, P. malariae, and P. ovale were identified in 53.3%, 22.9%, 3.6%, and 2.6% of cases, respectively. Twelve patients (0.9% of total) were infected by two or more species. The infecting species was unreported or undetermined in 212 (16.6%) cases. Compared with 2002, the number of reported malaria cases acquired in Asia (n = 177) and the Americas (n = 147) increased by 3.5% and 4.3% respectively, whereas the number of cases acquired in Africa (n = 840) decreased by 7.0%. Of 762 U.S. civilians who acquired malaria abroad, 132 (17.3%) reported that they had followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Ten patients became infected in the United States, including one probable transfusion-related, one in which epidemiologic investigations failed to identify any apparent mode of acquisition, and eight which were introduced cases as a result of local mosquitoborne transmission. Of the seven deaths attributed to malaria, five were caused by P. falciparum, and a species was not identified in the other two.Interpretation: The 4.4% decrease in malaria cases in 2003, compared with 2002, resulted primarily from a decrease in cases acquired in Africa, but this decrease was offset by an increase in the number of cases acquired in the Americas and Asia. This small decrease probably represents year-to-year variation in malaria cases, but also could have resulted from local changes in disease transmission, decreased travel to malaria-endemic regions, or fluctuation in reporting to state and local health departments. In the majority of reported cases, U.S. civilians who acquired infection abroad were not on an appropriate chemoprophylaxis regimen for the country in which they acquired malaria.Public Health Actions: Additional information was obtained concerning the seven fatal cases and the 10 infections acquired in the United States. Persons traveling to a malarious area should take one of the recommended chemoprophylaxis regimens appropriate for the region of travel, and travelers should use personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently experiences a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should include a blood-film test for malaria. Malaria infections can be fatal if not diagnosed and treated promptly. Recommendations concerning malaria prevention can be obtained from CDC by calling the Malaria Hotline at 770-488-7788 or by accessing CDC's Internet site at http://www.cdc.gov/travel. Recommendations concerning diagnosis of malaria and its treatment can be obtained by calling the Malaria Hotline or accessing CDC's Internet site at http://www.cdc.gov/malaria/diagnosis_treatment/treatment.htm [ABSTRACT FROM AUTHOR]

Comprehensive malaria case surveillance is necessary to achieve and sustain malaria elimination. In the Greater Mekong Subregion (GMS), the private sector plays a substantial role in malaria treatment. Yet, none of the six GMS countries collects complete case data from private sector points-of-care. Between 2016 and 2019, the GMS Elimination of Malaria through Surveillance program supported national malaria programs in Cambodia, Lao PDR, Myanmar, and Vietnam to execute elimination strategies by engaging the private sector in malaria case management, generating private sector case data, and integrating these data into national surveillance systems. The project enrolled 21,903 private sector outlets, covering between 52% and 80% of the private sector in targeted geographies, which were trained and equipped to perform rapid diagnostic tests (RDTs) and report malaria case data. By 2019, the private providers enrolled in the program reported a total of 3,521,586 suspected cases and 96,400 confirmed malaria cases into national surveillance systems, representing 16% of the total reported caseload by these countries (Cambodia, 25%; Lao PDR, 5%; Myanmar, 12%; Vietnam, 8%). Results demonstrated that with comprehensive support, such as training, provision of free or subsidized RDTs, first-line treatments, and routine supportive supervision, private providers can provide quality malaria case management and achieve high reporting rates.

Background: Private sector malaria programmes contribute to government-led malaria elimination strategies in Cambodia, Lao PDR, and Myanmar by increasing access to quality malaria services and surveillance data. However, reporting from private sector providers remains suboptimal in many settings. To support surveillance strengthening for elimination, a key programme strategy is to introduce electronic surveillance tools and systems to integrate private sector data with national systems, and enhance the use of data for decision-making. During 2013-2017, an electronic surveillance system based on open source software, District Health Information System 2 (DHIS2), was implemented as part of a private sector malaria case management and surveillance programme. The electronic surveillance system covered 16,000 private providers in Myanmar (electronic reporting conducted by 200 field officers with tablets), 710 in Cambodia (585 providers reporting through mobile app), and 432 in Laos (250 providers reporting through mobile app)., Methods: The purpose of the study was to document the costs of introducing electronic surveillance systems and mobile reporting solutions in Cambodia, Lao PDR, and Myanmar, comparing the cost in different operational settings, the cost of introduction and maintenance over time, and assessing the affordability and financial sustainability of electronic surveillance. The data collection methods included extracting data from PSI's financial and operational records, collecting data on prices and quantities of resources used, and interviewing key informants in each setting. The costing study used an ingredients-based approach and estimated both financial and economic costs., Results: Annual economic costs of electronic surveillance systems were $152,805 in Laos, $263,224 in Cambodia, and $1,310,912 in Myanmar. The annual economic cost per private provider surveilled was $82 in Myanmar, $371 in Cambodia, and $354 in Laos. Cost drivers varied depending on operational settings and number of private sector outlets covered in each country; whether purchased or personal mobile devices were used; and whether electronic (mobile) reporting was introduced at provider level or among field officers who support multiple providers for case reporting., Conclusion: The study found that electronic surveillance comprises about 0.5-1.5% of national malaria strategic plan cost and 7-21% of surveillance budgets and deemed to be affordable and financially sustainable.

Competing Interests: Competing interests: We have read and understood BMJ policy on declaration of interests and have no relevant interests to declare.

Between 2012 and 2017, the U.S. President's Malaria Initiative-funded MalariaCare project supported national malaria control programs in sub-Saharan Africa to implement a case management quality assurance (QA) system for malaria and other febrile illnesses. A major component of the system was outreach training and supportive supervision (OTSS), whereby trained government health personnel visited health facilities to observe health-care practices using a standard checklist, to provide individualized feedback to staff, and to develop health facility-wide action plans based on observation and review of facility registers. Based on MalariaCare's experience, facilitating visits to more than 5,600 health facilities in nine countries, we found that programs seeking to implement similar supportive supervision schemes should consider ensuring the following: 1) develop a practical checklist that balances information gathering and mentorship; 2) establish basic competency criteria for supervisors and periodically assess supervisor performance in the field; 3) conduct both technical skills training and supervision skills training; 4) establish criteria for selecting facilities to conduct OTSS and determine the appropriate frequency of visits; and 5) use electronic data collection systems where possible. Cost will also be a significant consideration: the average cost per OTSS visit ranged from $44 to $333. Significant variation in costs was due to factors such as travel time, allowances for government personnel, length of the visit, and involvement of central level officials. Because the cost of conducting supportive supervision prohibits regularly visiting all health facilities, internal QA measures could also be considered as alternative or complementary activities to supportive supervision.

Rapid diagnostic tests (RDTs) are one of the primary tools used for parasitological confirmation of suspected cases of malaria. To ensure accurate results, health-care workers (HCWs) must conduct the RDT test correctly. Trained supervisors visited 3,603 facilities to assess RDT testing performance and conduct outreach training and supportive supervision activities in eight African countries between 2015 and 2017, using a 12-point checklist to determine if key steps were being performed. The proportion of HCWs performing each step correctly improved between 1.1 and 21.0 percentage points between the first and third visits. Health-care worker scores were averaged to calculate facility scores, which were found to be high: the average score across all facilities was 85% during the first visit and increased to 91% during the third visit. A regression analysis of these facility scores estimated that, holding key facility factors equal, facility performance improved by 5.3 percentage points from the first to the second visit ( P < 0.001), but performance improved only by 0.6 percentage points ( P = 0.10) between the second and third visits. Factors strongly associated with higher scores included the presence of a laboratory worker at the facility and the presence of at least one staff member with previous formal training in malaria RDTs. Findings confirm that a comprehensive quality assurance system of training and supportive supervision consistently, and often significantly, improves RDT performance.

Although light microscopy is the reference standard for diagnosing malaria, maintaining skills over time can be challenging. Between 2015 and 2017, the U.S. President's Malaria Initiative-funded MalariaCare project supported outreach training and supportive supervision (OTSS) visits at 1,037 health facilities in seven African countries to improve performance in microscopy slide preparation, staining, and reading. During these visits, supervisors observed and provided feedback to health-care workers (HCWs) performing malaria microscopy using a 30-step checklist. Of the steps observed in facilities with at least three visits, the proportion of HCWs that performed each step correctly at baseline ranged from 63.2% to 94.2%. The change in the proportion of HCWs performing steps correctly by the third visit ranged from 16.7 to 23.6 percentage points ( n = 916 observations). To assess the overall improvement, facility scores were calculated based on the steps performed correctly during each visit. The mean score at baseline was 85.7%, demonstrating a high level of performance before OTSS. Regression analysis predicted an improvement in facility scores of 3.6 percentage points ( P < 0.001) after three visits across all countries. In reference-level facilities with consistently high performance on microscopy procedures and parasite detection, quality assurance (QA) mechanisms could prioritize more advanced skills, such as proficiency testing for parasite counting and species identification. However, in settings with high staff turnover and declining use of microscopy in favor of rapid diagnostic tests, additional supervision visits and/or additional QA measures may be required to improve and maintain performance.

Since 2010, the WHO has recommended that clinical decision-making for malaria case management be performed based on the results of a parasitological test result. Between 2015 and 2017, the U.S. President's Malaria Initiative-funded MalariaCare project supported the implementation of this practice in eight sub-Saharan African countries through 5,382 outreach training and supportive supervision visits to 3,563 health facilities. During these visits, trained government supervisors used a 25-point checklist to observe clinicians' performance in outpatient departments, and then provided structured mentoring and action planning. At baseline, more than 90% of facilities demonstrated a good understanding of WHO recommendations-when tests should be ordered, using test results to develop an accurate final diagnosis, severity assessment, and providing the correct prescription. However, significant deficits were found in history taking, conducting a physical examination, and communicating with patients and their caregivers. After three visits, worker performance demonstrated steady improvement-in particular, with checking for factors associated with increased morbidity and mortality: one sign of severe malaria (72.9-85.5%), pregnancy (81.1-87.4%), and anemia (77.2-86.4%). A regression analysis predicted an overall improvement in clinical performance of 6.3% ( P < 0.001) by the third visit. These findings indicate that in most health facilities, there is good baseline knowledge on the processes of quality clinical management, but further training and on-site mentoring are needed to improve the clinical interaction that focuses on second-order decision-making, such as severity of illness, management of non-malarial fever, and completing the patient-provider communication loop.

In December 2004, Togo was the first country to conduct a nationwide free insecticide-treated net (ITN) distribution as part of its National Integrated Child Health Campaign. Community-based cross-sectional surveys were conducted one and nine months post-campaign as part of a multidisciplinary evaluation of the nationwide distribution of ITNs to children 9-59 months of age to evaluate ITN ownership, equity, and use. Our results demonstrated that at one month post-campaign, 93.1% of all eligible children received an ITN. Household ITN ownership and equity increased significantly post-campaign. Nine months post-campaign, 78.6% of households with a child eligible to participate in the campaign retained at least one campaign net. Use by eligible children was 43.5% at one month post-campaign (during the dry season) and 52.9% at nine months post-campaign (during the rainy season). Household ownership of at least one ITN increased from 8.0% pre-campaign to 62.5% one month post-campaign. Together, these findings demonstrate that in this setting, increased household ITN ownership, equity, and retention can be achieved on a national scale through free ITN distribution during an integrated campaign.

Background: An evaluation of the short-term impact on childhood malaria morbidity of mass distribution of free long-lasting insecticidal nets (LLINs) to households with children aged 9-59 months as part of the Togo National Integrated Child Health Campaign., Methods: The prevalence of anaemia and malaria in children aged zero to 59 months was measured during two cross-sectional household cluster-sample surveys conducted during the peak malaria transmission, three months before (Sept 2004, n=2521) and nine months after the campaign (Sept 2005, n=2813) in three districts representative of Togo's three epidemiological malaria transmission regions: southern tropical coastal plains (Yoto), central fertile highlands (Ogou) and northern semi-arid savannah (Tone)., Results: In households with children<5 years of age, insecticide-treated net (ITN) ownership increased from <1% to >65% in all 3 districts. Reported ITN use by children during the previous night was 35.9%, 43.8% and 80.6% in Yoto, Ogou and Tone, respectively. Rainfall patterns were comparable in both years. The overall prevalence of moderate to severe anaemia (Hb<8.0 g/dL) was reduced by 28% (prevalence ratio [PR] 0.72, 95% CI 0.62-0.84) and mean haemoglobin was increased by 0.35 g/dL (95% CI 0.25-0.45).The effect was predominantly seen in children aged 18-59 months and in the two southern districts: PR (95% CI) for moderate to severe anaemia and clinical malaria: Yoto 0.62 (0.44-0.88) and 0.49 (0.35-0.75); Ogou 0.54 (0.37-0.79) and 0.85 (0.57-1.27), respectively. Similar reductions occurred in children<18 months in Ogou, but not in Yoto. No effect was seen in the semi-arid northern district despite a high malaria burden and ITN coverage., Conclusions: A marked reduction in childhood malaria associated morbidity was observed in the year following mass distribution of free LLINs in two of the three districts in Togo. Sub-national level impact evaluations will contribute to a better understanding of the impact of expanding national malaria control efforts.

Objectives: In December 2005 and March 2006, Niger conducted nationwide integrated campaigns to distribute polio vaccine and long lasting insecticide-treated nets (LLINs) to children <5 years of age. We evaluated the campaign effectiveness, net retention, insecticide-treated net (ITN) ownership, and usage., Methods: Two nationwide cross-sectional surveys in January 2006 (dry season) and September 2006 (rainy season), using a stratified two-stage cluster sampling design. We mapped selected communities, selected households by simple random sampling, and administered questionnaires by interviewers using personal digital assistants., Results: The first survey showed that ITN ownership in all households was 6.3% prior to the campaign, increasing to 65.1% after the campaign in the second survey. The second survey also showed that 73.4% of households with children <5 received an LLIN and that 97.7% of households that received > or = one LLIN retained it. The wealth equity ratio for ITN ownership in households with children <5 increased from 0.17 prior to the campaign to 0.79 afterward. During the dry season, 15.4% of all children <5 and 11.3% of pregnant women slept under an ITN, while during rainy season, 55.5% of children <5 and 48.2% of pregnant women slept under an ITN., Conclusions: Free distribution during the integrated campaign rapidly increased ITN ownership and decreased inequities between those in the highest and lowest wealth quintiles. Retention of ITNs was very high, and usage was high during malaria transmission season. However, ITN ownership and usage by vulnerable groups continues to fall short of RBM targets, and additional strategies are needed to increase ownership and usage.

We introduce an innovative method that uses personal digital assistants (PDAs) equipped with global positioning system (GPS) units in household surveys to select a probability-based sample and perform PDA-based interviews. Our approach uses PDAs with GPS to rapidly map all households in selected areas, choose a random sample, and navigate back to the sampled households to conduct an interview. We present recent field experience in two large-scale nationally representative household surveys to assess insecticide-treated bed net coverage as part of malaria control efforts in Africa. The successful application of this method resulted in statistically valid samples; quality-controlled data entry; and rapid aggregation, analyses, and availability of preliminary results within days of completing the field work. We propose this method as an alternative to the Expanded Program on Immunization cluster sample method when a fast, statistically valid survey is required in an environment with little census information at the enumeration area level.

A community-based baseline cross-sectional survey was conducted in three districts in Togo in September 2004 as part of a multidisciplinary evaluation of the impact of the Togo National Integrated Child Health Campaign. During this campaign, long-lasting-insecticide-treated bed nets (LLITNs) were distributed to households with children between 9 months and 5 years of age throughout the country in December 2004. The pre-intervention survey provided baseline malaria and anemia prevalence in children < 5 years of age during peak malaria transmission. Of 2,532 enrolled children from 1,740 households, 62.2% (1,352/2,172) were parasitemic and 84.4% (2,129/2,524) were anemic (hemoglobin < 11 g/dL). Moderate-to-severe anemia (< 8.0 g/dL) was found in 21.7% (543/2,524), with a peak prevalence in children 6-17 months of age and was strongly correlated with parasitemia (OR = 2.3, 95% CI: 1.8-2.5). Net ownership (mainly untreated) was 225/2,532 (8.9%). Subsequent nation-wide introduction of LLITNs and the introduction of artemisinin-based combination therapy have the potential to markedly reduce this burden of malaria.