Diagnosis of Human Trematode Infections.

Digenetic trematodes form a major group of human parasites, affecting a large number of humans, especially in endemic foci. Over 100 species have been reported infecting humans, including blood, lung, liver, and intestinal parasites. Traditionally, trematode infections have been diagnosed by parasitological methods based on the detection and the identification of eggs in different clinical samples. However, this is complicated due to the morphological similarity between eggs of different trematode species and other factors such as lack of sensitivity or ectopic locations of the parasites. Moreover, the problem is currently aggravated by migratory flows, international travel, international trade of foods, and changes in alimentary habits. Although efforts have been made for the development of immunological and molecular techniques, the detection of eggs through parasitological techniques remains as the gold standard for the diagnosis of trematodiases. In this chapter, we review the current status of knowledge on diagnostic techniques used when examining feces, urine, and sputum and also analyze the most relevant characteristics used to identify eggs with a quick key for the identification of eggs.

Economic impact of malaria-related hospitalizations in the United States, 2000-2014.

BACKGROUND: Despite its elimination in the early 1950s, about 1700 cases of malaria are reported in the US every year. Few studies have quantified the direct and indirect costs of imported malaria in the US. METHODS: Disparities in the mean and total hospital days, hospital charges, and hospital costs for malaria-related hospitalizations in the US by demographic, clinical, species, financial, geographic, and institutional characteristics were examined using the 2000-2014 Nationwide Inpatient Sample (NIS). Trends and potential predictors for length of stay and hospital charges and costs were identified using negative binomial regression and linear regression, respectively. RESULTS: From 2000 to 2014, 22,029 malaria cases resulted in 95,948 hospital days for malaria-related hospitalizations, $176,391,466 in total hospital costs, and $555,435,849 in total charges. Mean charges increased significantly over the study period. Males, Blacks, and patients aged 25-44years accounted for the highest direct and indirect costs. Older age and having severe malaria was associated with a longer length of stay. Older age, severe malaria, HIV infection, and longer lengths of stay were associated with higher charges and costs. CONCLUSIONS: Malaria resulted in substantial direct and indirect costs in the US. Primary and secondary prevention measures should be prioritized among high-risk groups to reduce the economic burden.

Risk factors for severe malaria among hospitalized patients in the United States, 2000-2014.

BACKGROUND: Factors associated with the development of severe malaria have not been well described for cases occurring in the United States (US). METHODS: Severe malaria hospitalizations data from the 2000-2014 Nationwide Inpatient Sample were analyzed. Frequencies were reported by demographic, clinical, species, financial, geographic, and institutional characteristics, and trends and disparities were identified. Logistic regression models were used to identify potential predictors for severe disease among those with malaria. RESULTS: From 2000 to 2014, there were an estimated 4823 severe malaria cases, representing 21.9% of all malaria-related hospitalizations, including 182 severe malaria deaths. Severe malaria was most common among inpatients who were male, Black, aged 45-64 years, and hospitalized in the South Atlantic division of the US. Older age was associated with higher odds of severe malaria, cerebral malaria, ARDS, severe anemia, and renal failure. Males had higher odds of developing renal failure and jaundice, while females had higher odds of developing severe anemia. HIV infection was associated with increased odds of severe malaria, severe anemia, and renal failure. CONCLUSION: Primary and secondary prevention measures, such as pre-travel consultations, chemoprophylaxis, and early diagnosis and treatment, should be emphasized and improved among high-risk prospective travelers to malaria endemic countries.

Malaria-Related Hospitalizations in the United States, 2000-2014.

Few data are available on the burden of malaria hospitalization in the United States. Study of malaria using hospital-based data can better define the impact of malaria and help inform prevention efforts. U.S. malaria cases identified from hospitalization discharge records in the 2000-2014 Nationwide Inpatient Sample were examined. Frequencies and population rates were reported by demographics, infecting species, clinical, financial, institutional, geographic, and seasonal characteristics, and disparities were identified. Time trends in malaria cases were assessed using negative binomial regression. From 2000 to 2014, there were an estimated 22,029 malaria-related hospitalizations (4.88 per 1 million population) in the United States, including 182 in-hospital deaths and 4,823 severe malaria cases. The rate of malaria-related hospitalizations did not change significantly over the study period. The largest number of malaria-related hospitalizations occurred in August. Malaria-related hospitalizations occurred disproportionately among patients who were male, black, or 25-44 years of age. Plasmodium falciparum accounted for the majority of malaria-related hospitalizations. On average, malaria patients were hospitalized for 4.36 days with charges of $25,789. Patients with a malaria diagnosis were more often hospitalized in the Middle Atlantic and South Atlantic census divisions, urban teaching, private not-for-profit, and large-bed-size hospitals. Malaria imposes a substantial disease burden in the United States. Enhanced primary and secondary prevention measures, including strategies to increase the use of pretravel consultations and prompt diagnosis and treatment are needed.

Severe and fatal central nervous system disease in humans caused by Baylisascaris procyonis, the common roundworm of raccoons: a review of current literature.

Baylisascaris procyonis, a parasitic infection of raccoons, causes severe neurologic disease in humans when infective eggs from raccoon feces are ingested. Definitive diagnosis is challenging, but can be made by isolation of larvae in brain biopsy or exclusion of other potential causes of eosinophilic meningoencephalitis. Prevention efforts are critical due to the lack of effective treatment.

Cysticercosis-related hospitalizations in the United States, 1998-2011.

Cysticercosis has become increasingly recognized as an important infection in the United States in recent decades. Despite its potential impact, there is a lack of comprehensive information on the nationwide burden of disease. To better define the burden of cysticercosis in the United States, we analyzed in-patient records using the Nationwide Inpatient Sample for 1998-2011 to estimate cysticercosis-related hospitalizations and patient/institutional characteristics. There were an estimated 33,060 (95% confidence interval [95% CI] = 29,610.5-36,510.3) cysticercosis-related hospitalizations nationwide, representing a hospitalization rate of 8.03 per million population. The highest proportion of cases were male (54.8%), Hispanic (62.0%), aged 18-44 (58.8%), and occurred in the West (45.1%). An estimated 459 deaths occurred, representing an in-hospital case-fatality rate of 1.4%. These findings indicate the burden of cysticercosis-related hospitalizations in the United States is considerable and may be greater than currently appreciated. Cysticercosis should be a nationally reportable disease.

Central nervous system and eye manifestations of infection with Baylisascaris procyonis.

Baylisascaris procyonis, a parasitic infection of raccoons, causes severe neurologic and ocular disease in humans when infectious eggs from raccoon feces are ingested. In the absence of a serologic test, definitive diagnosis is challenging but can be made by isolation of larvae in brain biopsy, direct visualization of the worm in the eye, or exclusion of other potential causes of eosinophilic meningoencephalitis. Currently, no effective treatment has been identified, making preventive efforts critical.

Baylisascaris procyonis: an emerging helminthic zoonosis.

Baylisascaris procyonis, a roundworm infection of raccoons, is emerging as an important helminthic zoonosis, principally affecting young children. Raccoons have increasingly become peridomestic animals living in close proximity to human residences. When B. procyonis eggs are ingested by a host other than a raccoon, migration of larvae through tissue, termed larval migrans, ensues. This larval infection can invade the brain and eye, causing severe disease and death. The prevalence of B. procyonis infection in raccoons is often high, and infected animals can shed enormous numbers of eggs in their feces. These eggs can survive in the environment for extended periods of time, and the infectious dose of B. procyonis is relatively low. Therefore, the risk for human exposure and infection may be greater than is currently recognized.

Cysticercosis-related deaths, California.

Cysticercosis is an increasingly important disease in the United States, but information on the occurrence of related deaths is limited. We examined data from California death certificates for the 12-year period 1989-2000. A total of 124 cysticercosis deaths were identified, representing a crude 12-year death rate of 3.9 per million population (95% confidence interval [CI] 3.2 to 4.6). Eighty-two (66%) of the case-patients were male; 42 (34%) were female. The median age at death was 34.5 years (range 7-81 years). Most patients (107, 86.3%) were foreign-born, and 90 (72.6%) had emigrated from Mexico. Seventeen (13.7%) deaths occurred in U.S.-born residents. Cysticercosis death rates were higher in Latino residents of California (13.0/106) than in other racial/ethnic groups (0.4/106), in males (5.2/106) than in females (2.7/106), and in persons >14 years of age (5.0/106). Cysticercosis is a preventable cause of premature death, particularly among young Latino persons in California and may be a more common cause of death in the United States than previously recognized.