Infectious Diseases News Brief - July 9, 2010

[Current Issue -Table of contents]

Quantification and Spread of Pneumocystis jirovecii in the Surrounding Air of Patients with Pneumocystis Pneumonia

Background

Airborne transmission of Pneumocystis has been demonstrated in animal models and is highly probable in humans. However, information concerning burdens of Pneumocystis jirovecii (human-derived Pneumocystis) in exhaled air from infected patients is lacking. The researchers’ objective was to evaluate P. jirovecii air diffusion in patients with Pneumocystis pneumonia.

Methods

Patients admitted with Pneumocystis pneumonia were prospectively enrolled from 9 January 2008 to 21 July 2009. Air samples (1.5 m3) were collected on liquid medium with a commercial sampler at 1-, 3-, 5-, and 8-m distances from patients’ heads. Air control samples were collected away from Pneumocystis pneumonia patient wards and outdoors. Samples were examined for P. jirovecii detection and quantification using a real-time polymerase chain reaction assay targeting the mitochondrial large subunit ribosomal RNA gene.

Results

Forty patients were diagnosed as having Pneumocystis pneumonia. Air sampling was performed in the environment for 19 of them. At a 1-m distance from patients’ heads, P. jirovecii DNA was detected in 15 (79.8%) of 19 patients, with fungal burdens ranging from to gene copies/m3. These levels decreased with distance from the patients ( ). Nevertheless, 4 (33.3%) of the 12 samples taken at 8 m, in the corridor adjacent to their room, were still positive. Forty control samples were collected and remained negative.

Conclusion

This study provides the first quantitative data on the spread of P. jirovecii in exhaled air from infected patients. It sustains the risk of P. jirovecii direct transmission in close contact with patients with Pneumocystis pneumonia and leads the way for initiating a quantitative risk assessment for airborne transmission of P. jirovecii.

Clinical Infectious Diseases 2010;51:259–265
http://www.journals.uchicago.edu/toc/cid/2010/51/3

Malaria Surveillance --- United States, 2008

Problem/Condition

Malaria in humans is caused by intraerythrocytic protozoa of the genus Plasmodium. These parasites are transmitted by the bite of an infective female Anopheles species mosquito. The majority of malaria infections in the United States occur among persons who have travelled to areas with ongoing malaria transmission. In the United States, cases can occur through exposure to infected blood products, congenital transmission, or local mosquito-borne transmission. Malaria surveillance is conducted to identify episodes of local transmission and to guide prevention recommendations for travellers.

Period Covered

This report summarizes cases in patients with onset of illness in 2008 and summarizes trends during previous years.

Description of System

Malaria cases diagnosed by blood film, polymerase chain reaction, or rapid diagnostic tests are mandated to be reported to local and state health departments by health-care providers or laboratory staff members. Case investigations are conducted by local and state health departments, and reports are transmitted to CDC through the National Malaria Surveillance System (NMSS), National Notifiable Diseases Surveillance System (NNDSS), and direct CDC consultations. Data from these reporting systems are the basis for this report.

Results

CDC received reports of 1,298 cases of malaria with an onset of symptoms in 2008 among patients in the United States, a decrease of 13.8% from the 1,505 cases reported for 2007 (p<0.001). These cases included one transfusion-related case, one congenital case, and two fatal cases. Plasmodium falciparum, P. vivax, P. malariae, and P. ovale were identified in 40.6%, 14.6%, 1.5%, and 1.4% of cases, respectively. The first documented case of simian malaria, P. knowlesi, was reported in a U.S. traveler. Eight (0.6%) of the 1,298 patients were infected by two or more species. The infecting species was unreported or undetermined in 41.2% of cases. Based on estimated volume of travel from the World Tourism Organization, the highest estimated relative case rates of malaria among travelers occurred among those returning from countries in West Africa. A total of 508 U.S. civilians acquired malaria abroad; among the 480 civilians for whom chemoprophylaxis information was known, 344 (71.7%) reported that they had not followed a chemoprophylactic drug regimen recommended by CDC for the area to which they had traveled. Fourteen cases were reported in pregnant women, among whom none adhered to a complete prevention drug regimen.

Interpretation

A significant decrease in the number of malaria cases occurred from 2007 to 2008. No change occurred in the proportions of cases caused by the various Plasmodium species. U.S. civilians traveling to countries in West Africa had the highest estimated relative case rates. In the majority of reported cases, U.S. civilians who acquired malaria abroad had not adhered to a chemoprophylaxis regimen that was appropriate for the country in which they acquired the infection.

Public Health Actions

Persons traveling to an area in which malaria is endemic should take steps to prevent malaria, which might include taking one of the recommended chemoprophylaxis regimens appropriate for the region of travel and using personal protection measures to prevent mosquito bites. Any person who has been to a malarious area and who subsequently develops a fever or influenza-like symptoms should seek medical care immediately and report their travel history to the clinician; investigation should always include blood-film tests for malaria with results available immediately. Malaria infections can be fatal if not diagnosed and treated promptly.

Morbidity and Mortality Weekly Report (MMWR): Surveillance Summaries
June 25, 2010 / 59(SS07);1-15
http://www.cdc.gov/mmwr/preview/mmwrhtml/ss5907a1.htm?s_cid=ss5907a1_w

Sexually Transmitted Diseases Among Users of Erectile Dysfunction Drugs: Analysis of Claims Data

Background

Pharmacologic treatments for erectile dysfunction (ED) have gained popularity among middle-aged and older men. Increased sexual activity among those who use these drugs raises concerns about sexually transmitted diseases (STDs). Objective of the study was to examine the rates of STDs in men who use and do not use ED drugs.

Method

It was a retrospective cohort study. Database of claims from 1997 to 2006 for 1 410 806 men older than age 40 years with private, employer-based insurance from 44 large companies were used. 33 968 men with at least 1 filled prescription for an ED drug and 1 376 838 patients with no prescription were included for the study. Measurements used for analysis purposes were STD prevalence among users and nonusers of ED drugs.

Results

Users of ED drugs had higher rates of STDs than nonusers the year before initiating ED drug therapy (214 vs. 106 annually per 100 000 persons; P = 0.003) and the year after (105 vs. 65; P = 0.004). After adjustment for age and other comorbid conditions, users of ED drugs had an odds ratio (OR) for an STD of 2.80 (95% CI, 2.10 to 3.75) in the year before initiating drug therapy; the OR was 2.65 (CI, 1.84 to 3.81) in the year after. These differences were largely due to infections with HIV. The OR for HIV infection was 3.32 (CI, 2.38 to 4.36) in the year before and 3.19 (CI, 2.11 to 4.83) in the year after an ED drug prescription was filled. Significant changes in STD rates from the year before to the year after the first ED drug prescription was filled were not documented (adjusted OR for STD for users before vs. after the first ED drug prescription was filled, 0.96 [CI, 0.87 to 1.06]).

Conclusion and Limitation

Men who use ED drugs have higher rates of STDs, particularly HIV infection, both in the year before and after use of these drugs. The observed association between ED drug use and STDs may have more to do with the types of patients using ED drugs rather than a direct effect of ED drug availability on STD rates. Counseling about safe sexual practices and screening for STDs should accompany the prescription of ED drugs. Selection bias precludes conclusions about whether use of ED treatments directly leads to increases in STDs.

Ann Intern Med July 6, 2010 153:I-44;
http://www.annals.org/