Trends in Number and Distribution of COVID-19 Hotspot Counties - United States, March 8-July 15, 2020.

The geographic areas in the United States most affected by the coronavirus disease 2019 (COVID-19) pandemic have changed over time. On May 7, 2020, CDC, with other federal agencies, began identifying counties with increasing COVID-19 incidence (hotspots) to better understand transmission dynamics and offer targeted support to health departments in affected communities. Data for January 22-July 15, 2020, were analyzed retrospectively (January 22-May 6) and prospectively (May 7-July 15) to detect hotspot counties. No counties met hotspot criteria during January 22-March 7, 2020. During March 8-July 15, 2020, 818 counties met hotspot criteria for ≥1 day; these counties included 80% of the U.S. population. The daily number of counties meeting hotspot criteria peaked in early April, decreased and stabilized during mid-April-early June, then increased again during late June-early July. The percentage of counties in the South and West Census regions* meeting hotspot criteria increased from 10% and 13%, respectively, during March-April to 28% and 22%, respectively, during June-July. Identification of community transmission as a contributing factor increased over time, whereas identification of outbreaks in long-term care facilities, food processing facilities, correctional facilities, or other workplaces as contributing factors decreased. Identification of hotspot counties and understanding how they change over time can help prioritize and target implementation of U.S. public health response activities.

What Do We Know About Chagas Disease in the United States?

Chagas disease, caused by the parasite Trypanosoma cruzi, affects more than 5 million people worldwide leading to serious heart and gastrointestinal disease in a proportion of chronically infected patients. Important modes of transmission include vector-borne, congenital, and via blood transfusion or organ transplant from an infected donor. Vector-borne transmission of Chagas disease occurs in the Americas, including the southern half of North America, where the specific vector insects (triatomines), T. cruzi, and infected reservoir mammalian hosts are found. In the United States, there are estimated to be at least 300,000 cases of chronic Chagas disease among people originally from countries of Latin America where Chagas disease is endemic. Fewer than 30 cases of locally acquired infection have been documented in the United States, although a sylvatic transmission cycle has been known to exist in this country for at least a century. Studies defining risks for locally acquired infection and effective prevention strategies are needed to help prevent domestic transmission of T. cruzi To help address Chagas disease in the United States, improved health-care provider awareness and knowledge, better tools for screening and diagnosing patients, and wider availability of treatment drugs are needed.

Neglected parasitic infections in the United States: toxoplasmosis.

Toxoplasma gondii is a leading cause of severe foodborne illness in the United States. Population-based studies have found T. gondii infection to be more prevalent in racial/ethnic minority and socioeconomically disadvantaged groups. Soil contaminated with cat feces, undercooked meat, and congenital transmission are the principal sources of infection. Toxoplasmosis-associated illnesses include congenital neurologic and ocular disease; acquired illness in immunocompetent persons, most notably ocular disease; and encephalitis or disseminated disease in immunosuppressed persons. The association of T. gondii infection with risk for mental illness is intriguing and requires further research. Reduction of T. gondii in meat, improvements in hygiene and food preparation practices, and reduction of environmental contamination can prevent toxoplasmosis, but more research is needed on how to implement these measures. In addition, screening and treatment may help prevent toxoplasmosis or reduce the severity of disease in some settings.

Neglected parasitic infections in the United States: toxocariasis.

Toxocariasis is a preventable parasitic disease that is caused by the dog and cat roundworms Toxocara cani and T. cati, respectively. Humans become infected when they accidently ingest infectious Toxocara eggs commonly found in contaminated soil; children are most often affected. Clinical manifestations of Toxocara infection in humans include ocular toxocariasis and visceral toxocariasis. Although infection with Toxocara can cause devastating disease, the burden of toxocariasis in the United States population remains unknown. In addition, risk factors for acquiring infection need to be better defined, and research needs to be conducted to better understand the pathophysiology and clinical course of toxocariasis. Development of diagnostic tests would enable clinicians to detect active infection, and determination of optimal drug regiments would ensure patients were appropriately treated. Addressing these public health gaps is necessary to understand and address the impact of toxocariasis in the United States.

Presumptive treatment and medical screening for parasites in refugees resettling to the United States.

More than 50,000 refugees are resettled to the United States annually, many from areas highly endemic for parasites. Some of these infections present little clinical consequence after migration, but others are responsible for morbidity and mortality. The Centers for Disease Control and Prevention has issued predeparture presumptive treatment and postarrival medical guidelines for the management of parasites. Although these guidelines are evidence based, there remain significant challenges to presumptive treatment programs in refugees. Gaps in the evidence continue; resettling populations are continually changing, thus altering the epidemiology; and there are logistical and cost barriers to fully implementing recommendations. This article will review the evolution and status of current guidelines, as well as identify gaps and challenges to full implementation. It is imperative for clinicians serving this population to be familiar with interventions received by refugees, since previous treatment will impact screening, diagnostic evaluation, and treatment decisions.

Clinical, epidemiologic, histopathologic and molecular features of an unexplained dermopathy.

BACKGROUND: Morgellons is a poorly characterized constellation of symptoms, with the primary manifestations involving the skin. We conducted an investigation of this unexplained dermopathy to characterize the clinical and epidemiologic features and explore potential etiologies. METHODS: A descriptive study was conducted among persons at least 13 years of age and enrolled in Kaiser Permanente Northern California (KPNC) during 2006-2008. A case was defined as the self-reported emergence of fibers or materials from the skin accompanied by skin lesions and/or disturbing skin sensations. We collected detailed epidemiologic data, performed clinical evaluations and geospatial analyses and analyzed materials collected from participants' skin. RESULTS: We identified 115 case-patients. The prevalence was 3.65 (95% CI = 2.98, 4.40) cases per 100,000 enrollees. There was no clustering of cases within the 13-county KPNC catchment area (p = .113). Case-patients had a median age of 52 years (range: 17-93) and were primarily female (77%) and Caucasian (77%). Multi-system complaints were common; 70% reported chronic fatigue and 54% rated their overall health as fair or poor with mean Physical Component Scores and Mental Component Scores of 36.63 (SD = 12.9) and 35.45 (SD = 12.89), respectively. Cognitive deficits were detected in 59% of case-patients and 63% had evidence of clinically significant somatic complaints; 50% had drugs detected in hair samples and 78% reported exposure to solvents. Solar elastosis was the most common histopathologic abnormality (51% of biopsies); skin lesions were most consistent with arthropod bites or chronic excoriations. No parasites or mycobacteria were detected. Most materials collected from participants' skin were composed of cellulose, likely of cotton origin. CONCLUSIONS: This unexplained dermopathy was rare among this population of Northern California residents, but associated with significantly reduced health-related quality of life. No common underlying medical condition or infectious source was identified, similar to more commonly recognized conditions such as delusional infestation.

Doxycycline for malaria chemoprophylaxis and treatment: report from the CDC expert meeting on malaria chemoprophylaxis.

Doxycycline, a synthetically derived tetracycline, is a partially efficacious causal prophylactic (liver stage of Plasmodium) drug and a slow acting blood schizontocidal agent highly effective for the prevention of malaria. When used in conjunction with a fast acting schizontocidal agent, it is also highly effective for malaria treatment. Doxycycline is especially useful as a prophylaxis in areas with chloroquine and multidrug-resistant Plasmodium falciparum malaria. Although not recommended for pregnant women and children < 8 years of age, severe adverse events are rarely reported for doxycycline. This report examines the evidence behind current recommendations for the use of doxycycline for malaria and summarizes the available literature on its safety and tolerability.

Associations between peripheral Plasmodium falciparum malaria parasitemia, human immunodeficiency virus, and concurrent helminthic infection among pregnant women in Malawi.

Approximately 2 billion persons worldwide are infected with schistosomiasis and soil-transmitted helminths (STH), many in areas where endemic malaria transmission coexists. Few data exist on associations between these infections. Nested within a larger clinical trial, primigravid and secundigravid women provided blood samples for human immunodeficiency virus (HIV) testing and peripheral malaria films and stool and urine for evaluation of STH and Schistosoma spp. during their initial antenatal clinic visit. The most common parasitic infections were malaria (37.6%), S. haematobium (32.3%), and hookworm (14.4%); 14.2% of women were HIV-infected. S. haematobium infection was associated with lower malarial parasite densities (344 versus 557 parasites/µL blood; P < 0.05). In multivariate analysis, HIV and hookworm infection were independently associated with malaria infection (adjusted odds ratio = 1.9 and 95% confidence interval = 1.2-3.0 for HIV; adjusted odds ratio = 1.9 and 95% confidence interval = 1.03-3.5 for hookworm). Concurrent helminthic infection had both positive and negative effects on malaria parasitemia among pregnant women in Malawi.

Pharmacokinetics of sulfadoxine-pyrimethamine in HIV-infected and uninfected pregnant women in Western Kenya.

BACKGROUND: Sulfadoxine-pyrimethamine (SP) is among the most commonly used antimalarial drugs during pregnancy, yet the pharmacokinetics of SP are unknown in pregnant women. HIV-infected (HIV(+)) women require more frequent doses of intermittent preventive therapy with SP than do HIV-uninfected (HIV(-)) women. We investigated whether this reflects their impaired immunity or an HIV-associated alteration in the disposition of SP. METHODS: Seventeen pregnant HIV(-) women and 16 pregnant HIV(+) women received a dose of 1500 mg of sulfadoxine and 75 mg of pyrimethamine. Five HIV(-) and 6 HIV(+) postpartum women returned 2-3 months after delivery for another dose. The pharmacokinetics of sulfadoxine and pyrimethamine were compared between these groups. RESULTS: HIV status did not affect the area under the curve (AUC(0-->infinity)) or the half-lives of sulfadoxine or pyrimethamine in prepartum or postpartum women, although partum status did have a significant affect on sulfadoxine pharmacokinetics. Among prepartum women, the median half-life for sulfadoxine was significantly shorter than that observed in postpartum women (148 vs 256 h; P<.001), and the median AUC(0-->infinity) was ~40% lower (22,816 vs 40,106 microg/mL/h, P<.001). HIV status and partum status did not show any significant influence on pyrimethamine pharmacokinetics. CONCLUSION: Pregnancy significantly modifies the disposition of SP, whereas HIV status has little influence on pharmacokinetic parameters in pregnant women.

Safety and toxicity of sulfadoxine/pyrimethamine: implications for malaria prevention in pregnancy using intermittent preventive treatment.

Plasmodium falciparum infection during pregnancy is strongly associated with maternal anaemia and low birth weight, contributing to substantial morbidity and mortality in sub-Saharan Africa. Intermittent preventive treatment in pregnancy with sulfadoxine/pyrimethamine (IPTp-SP) has been one of the most effective approaches to reduce the burden of malaria during pregnancy in Africa. IPTp-SP is based on administering >or=2 treatment doses of sulfadoxine/pyrimethamine to pregnant women at predefined intervals after quickening (around 18-20 weeks). Randomised, controlled trials have demonstrated decreased rates of maternal anaemia and low birth weight with this approach. The WHO currently recommends IPTp-SP in malaria-endemic areas of sub-Saharan Africa. However, implementation has been suboptimal in part because of concerns of potential drug toxicities. This review evaluates the toxicity data of sulfadoxine/pyrimethamine, including severe cutaneous adverse reactions, teratogenicity and alterations in bilirubin metabolism. Weekly sulfadoxine/pyrimethamine prophylaxis is associated with rare but potentially fatal cutaneous reactions. Fortunately, sulfadoxine/pyrimethamine use in IPTp programmes in Africa, with 2-4 treatment doses over 6 months, has been well tolerated in multiple IPTp trials. However, sulfadoxine/pyrimethamine should not be administered concurrently with cotrimoxazole given their redundant mechanisms of action and synergistic worsening of adverse drug reactions. Therefore, HIV-infected pregnant women in malaria endemic areas who are already receiving cotrimoxazole prophylaxis should not also receive IPTp-SP. Although folate antagonist use in the first trimester is associated with neural tube defects, large case-control studies have demonstrated that sulfadoxine/pyrimethamine administered as IPTp (exclusively in the second and third trimesters and after organogenesis) does not result in an increased risk of teratogenesis. Folic acid supplementation is recommended for all pregnant women to reduce the rate of congenital anomalies but high doses of folic acid (5 mg/day) may interfere with the antimalarial efficacy of sulfadoxine/pyrimethamine. However, the recommended standard dose of folic acid supplementation (0.4 mg/day) does not affect antimalarial efficacy and may provide the optimal balance to prevent neural tube defects and maintain the effectiveness of IPTp-SP. No clinical association between sulfadoxine/pyrimethamine use and kernicterus has been reported despite the extensive use of sulfadoxine/pyrimethamine and related compounds to treat maternal malaria and congenital toxoplasmosis in near-term pregnant women and newborns. Although few drugs in pregnancy can be considered completely safe, sulfadoxine/pyrimethamine - when delivered as IPTp - has a favourable safety profile. Improved pharmacovigilance programmes throughout Africa are now needed to confirm its safety as access to IPTp-SP increases. Given the documented benefits of IPTp-SP in malaria endemic areas of Africa, access to this treatment for pregnant women should continue to expand.

Treatment of malaria in the United States: a systematic review.

CONTEXT: Many US clinicians and laboratory personnel are unfamiliar with the diagnosis and treatment of malaria. OBJECTIVES: To examine the evidence base for management of uncomplicated and severe malaria and to provide clinicians with practical recommendations for the diagnosis and treatment of malaria in the United States. EVIDENCE ACQUISITION: Systematic MEDLINE search from 1966 to 2006 using the search term malaria (with the subheadings congenital, diagnosis, drug therapy, epidemiology, and therapy). Additional references were obtained from searching the bibliographies of pertinent articles and by reviewing articles suggested by experts in the treatment of malaria in North America. EVIDENCE SYNTHESIS: Important measures to reduce morbidity and mortality from malaria in the United States include the following: obtaining a travel history, considering malaria in the differential diagnosis of fever based on the travel history, and prompt and accurate diagnosis and treatment. Chloroquine remains the treatment of choice for Plasmodium falciparum acquired in areas without chloroquine-resistant strains. In areas with chloroquine resistance, a combination of atovaquone and proguanil or quinine plus tetracycline or doxycycline or clindamycin are the best treatment options. Chloroquine remains the treatment of choice for all other malaria species, with the exception of P vivax acquired in Indonesia or Papua New Guinea, in which case atovaquone-proguanil is best, with mefloquine or quinine plus tetracycline or doxycycline as alternatives. Quinidine is currently the recommended treatment for severe malaria in the United States because the artemisinins are not yet available. Severe malaria occurs when a patient with asexual malaria parasitemia, and no other confirmed cause of symptoms, has 1 or more designated clinical or laboratory findings. The only adjunctive measure recommended in severe malaria is exchange transfusion. CONCLUSIONS: Malaria remains a diagnostic and treatment challenge for US clinicians as increasing numbers of persons travel to and emigrate from malarious areas. A strong evidence base exists to help clinicians rapidly initiate appropriate therapy and minimize the major mortality and morbidity burdens caused by this disease.

Atovaquone-proguanil: report from the CDC expert meeting on malaria chemoprophylaxis (II).

The fixed dose combination of atovaquone and proguanil hydrochloride, marketed under the trade name Malarone, is the most recently approved agent in North America for the prevention and treatment of chloroquine- and multi-drug resistant Plasmodium falciparum malaria. In both adult and pediatric populations, atovaquone-proguanil demonstrates consistently high protective efficacy against P. falciparum, and in treatment trials, cure rates exceed 93%. Only a handful of genetically confirmed treatment failures have been reported to date. Atovaquone-proguanil has an excellent safety profile during both prophylaxis and treatment courses, with severe adverse events rarely reported. This topical review will examine the evidence behind the current indications for use of atovaquone-proguanil, and will summarize the current body of literature surrounding safety and tolerability.

A randomized controlled trial of folate supplementation when treating malaria in pregnancy with sulfadoxine-pyrimethamine.

OBJECTIVES: Sulfadoxine-pyrimethamine (SP) is an antimalarial drug that acts on the folate metabolism of the malaria parasite. We investigated whether folate (FA) supplementation in a high or a low dose affects the efficacy of SP for the treatment of uncomplicated malaria in pregnant women. DESIGN: This was a randomized, placebo-controlled, double-blind trial. SETTING: The trial was carried out at three hospitals in western Kenya. PARTICIPANTS: The participants were 488 pregnant women presenting at their first antenatal visit with uncomplicated malaria parasitaemia (density of >or= 500 parasites/microl), a haemoglobin level higher than 7 g/dl, a gestational age between 17 and 34 weeks, and no history of antimalarial or FA use, or sulfa allergy. A total of 415 women completed the study. INTERVENTIONS: All participants received SP and iron supplementation. They were randomized to the following arms: FA 5 mg, FA 0.4 mg, or FA placebo. After 14 days, all participants continued with FA 5 mg daily as per national guidelines. Participants were followed at days 2, 3, 7, 14, 21, and 28 or until treatment failure. OUTCOME MEASURES: The outcomes were SP failure rate and change in haemoglobin at day 14. RESULTS: The proportion of treatment failure at day 14 was 13.9% (19/137) in the placebo group, 14.5% (20/138) in the FA 0.4 mg arm (adjusted hazard ratio [AHR], 1.07; 98.7% confidence interval [CI], 0.48 to 2.37; p = 0.8), and 27.1% (38/140) in the FA 5 mg arm (AHR, 2.19; 98.7% CI, 1.09 to 4.40; p = 0.005). The haemoglobin levels at day 14 were not different relative to placebo (mean difference for FA 5 mg, 0.17 g/dl; 98.7% CI, -0.19 to 0.52; and for FA 0.4 mg, 0.14 g/dl; 98.7% CI, -0.21 to 0.49). CONCLUSIONS: Concomitant use of 5 mg FA supplementation compromises the efficacy of SP for the treatment of uncomplicated malaria in pregnant women. Countries that use SP for treatment or prevention of malaria in pregnancy need to evaluate their antenatal policy on timing or dose of FA supplementation.

Primaquine: report from CDC expert meeting on malaria chemoprophylaxis I.

Primaquine phosphate has been used for preventing relapse of Plasmodium vivax and P. ovale malaria since the early 1950s, based on its ability to kill latent (hypnozoite) and developing liver stages of these parasites. There are three uses for primaquine in malaria: radical cure of established infection with P. vivax or P. ovale malaria; presumptive anti-relapse therapy (PART; terminal prophylaxis) in persons with extensive exposure to these parasites; and primary prophylaxis against all malaria species. All persons for whom primaquine is being considered must have a glucose-6-phosphate dehydrogenase (G6PD) enzyme level checked before use, and persons who have a deficiency of G6PD must not take primaquine for prophylaxis or PART. The recommended adult dose for PART based on clinical trials and expert opinion is 30 mg base daily for 14 days, started on return from a malarious region and overlapping with a blood schizonticide. The adult dose for primary prophylaxis is 30 mg daily begun 1 day before travel and continued for 7 days after return. This review will examine the evidence for these recommendations.

Malaria prevention during pregnancy: assessing the disease burden one year after implementing a program of intermittent preventive treatment in Koupela District, Burkina Faso.

The World Health Organization recommends that pregnant women in malaria-endemic areas receive >or= 2 doses of intermittent preventive treatment with sulfadoxine-pyrimethamine (IPTp/SP) in the second and third trimesters of pregnancy to prevent maternal anemia, placental parasitemia, and low birth weight (LBW). In 2001, a program evaluation in Koupéla District, Burkina Faso demonstrated that despite widespread use of chloroquine chemoprophylaxis, the burden of malaria during pregnancy remained high. In 2003, the Burkina Faso Ministry of Health piloted a program of IPTp/SP (three doses) and accelerated distribution of insecticide-treated nets (ITN) to pregnant women in Koupéla District. In 2004, a follow-up program evaluation was conducted. Coverage with >or= 1 doses of IPTp/SP was high among women attending antenatal clinics (ANCs) (96.2%) and delivery units (DUs) (93.5%); ITN ownership was moderately high (ANC = 53.9%, DU = 61.6%). In multivariate analysis, >or= 1 dose of IPTp/SP was associated with a significant reduction in the prevalence of peripheral parasitemia at ANCs (risk ratio [RR] = 0.49, P = 0.008), >or= 2 doses of IPTp/SP were associated with a reduction in the prevalence of placental parasitemia (RR = 0.56, P = 0.02), and three doses of IPTp/SP were associated with a reduced risk of LBW (RR = 0.51, P = 0.04). The proportions of women at ANCs with peripheral parasitemia and anemia were significantly lower in 2004 than in 2001 (RR = 0.53, P = 0.001 and RR = 0.78, P = 0.003, respectively). The proportions of women at DUs with peripheral and placental parasitemia were also significantly lower in 2004 than in 2001 (RR = 0.66, P < 0.0001 and RR = 0.71, P = 0.0002, respectively). These data suggest that a package of IPTp/SP and ITNs is effective in reducing the burden of malaria during pregnancy in Burkina Faso.

Randomized trial of 2-dose versus monthly sulfadoxine-pyrimethamine intermittent preventive treatment for malaria in HIV-positive and HIV-negative pregnant women in Malawi.

BACKGROUND: Intermittent preventive treatment during pregnancy (IPTp) with sulfadoxine-pyrimethamine (SP) decreases placental malaria parasitemia and associated maternal anemia, premature delivery, and low birth weight. However, the optimal regimen in the setting of a high prevalence of human immunodeficiency virus (HIV) infection remains unclear. METHODS: In Malawi, where the efficacy of SP for the treatment of malaria in children is decreasing, we conducted a randomized, nonblinded study to compare the efficacy of monthly SP IPTp with a 2-dose regimen for the prevention of placental parasitemia in HIV-positive and -negative primigravid and secundigravid women. RESULTS: Of HIV-positive women, 7.8% who received monthly SP had placental malaria, compared with 21.5% of those who received 2-dose SP (relative risk [RR], 0.36 [95% confidence interval {CI}, 0.17-0.79]). Of HIV-negative women, 2.3% who received monthly SP and 6.3% who received 2-dose SP had placental malaria (RR, 0.37 [95% CI, 0.11-1.19]). Less than 1% of women reported adverse drug reactions, with no increase in HIV-positive women or those who received monthly SP. CONCLUSIONS: In HIV-positive pregnant women, monthly SP IPTp is more efficacious than a 2-dose regimen in preventing placental malaria. The study also demonstrates the continued efficacy of SP for the prevention of placental malaria, even in the face of its decreasing efficacy for the treatment of malaria in children. In areas with intense transmission of falciparum malaria and a high prevalence of HIV infection, monthly SP IPTp should be adopted.

Malaria surveillance--United States, 2004.

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.htm or by calling the Malaria Hotline.

Prevention of malaria during pregnancy in West Africa: policy change and the power of subregional action.

BACKGROUND: Despite a broadening consensus about the effectiveness of intermittent preventive treatment (IPTp) in preventing the adverse outcomes of malaria during pregnancy, policy change to IPTp was initially limited to East Africa. In West Africa, where the policy change process for the prevention of malaria during pregnancy started much later, IPTp has been taken up swiftly. OBJECTIVE: To describe the factors that contributed to the rapid adoption of policies to prevent malaria during pregnancy in West Africa. RESULTS AND CONCLUSION: Several factors appear to have accelerated the process: (1) recognition of the extent of the problem of malaria during pregnancy and its adverse consequences; (2) a clear, evidence-based program strategy strongly articulated by an important multilateral organization (World Health Organization); (3) subregionally generated evidence to support the proposed strategy; (4) a subregional forum for dissemination of data and discussion regarding the proposed policy changes; (5) widespread availability of the proposed intervention drug (sulfadoxine-pyrimethamine); (6) technical support from reputable and respected institutions in drafting new policies and planning for implementation; (7) donor support for pilot experiences in integrating proposed policy change into a package of preventive services; and (8) financial support for scaling up the proposed interventions.

Malaria surveillance--United States, 2003.

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 ACTION: 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.