Updates

By Carol A. Kemper, MD, FACP, Section Editor: Updates, Clinical Associate Professor of Medicine, Stanford University, Division of Infectious Diseases; Santa Clara Valley Medical Center, is Associate Editor for Infectious Disease Alert.

Norovirus bounces between NBA players

Source: Desai R, et al. Transmission of norovirus among NBA players and staff, Winter 2010-2011. CID 2011; 53: 1115-1117.

Beginning in November 2010, players from several NBA teams were reported as suffering from the "stomach flu". An investigation was launched, querying 400 players and 378 staff members whether they had experienced nausea and/or vomiting sometime between November 10 and December 20. In total, 21 players and 3 staff members met the case definition for acute gastroenteritis from norovirus, based on the presence of symptoms with or without a positive RT-PCR stool test for norovirus. These 24 individuals represented 13 different teams from 11 different states.

The outbreak occurred between November 28 through December 8. Four teams had multiple cases with a total of 15 affected individuals. There was sufficient information available to indicate that 4 of these players were primary cases and 9 were secondary cases. Three of the four primary cases reported close contact with other members of the team during their illness, including contact in the locker rooms or travel together. One reported vomiting while en route to a game.

The authors identified 49 NBA games played during the 11-day outbreak. Two of these games were suspicious for team-to-team transmission of norovirus infection from a "donor team", with players with subsequently confirmed norovirus playing in those games. The authors examined 10 years of NBA "injury" data reports, and found that gastroenteritis was the second most common non-play-related injury in the NBA. They recommend that players with acute gastroenteritis symptoms be segregated from teammates, with restricted play, and strict personal hygiene and handwashing precautions during illness and for a good 24-72 hours after recovery.

A fluke of infertility ?

Source: Bailey SL, et al. Fluke Infertility: The late cost of a quick swim. J Travel Med 2011;18(1):61-62.

These authors describe two previously healthy, asymptomatic young British women who presented with upper genital tract disease, one during infertility work-up, which was surprising due to schistosomiasis acquired many years earlier.

The first was a 43 year-old woman undergoing infertility evaluation, including a normal hysterosalpingogram. Within a few weeks of that study, she developed suprapubic pain and cervical bleeding. Dense adhesions of the fallopian tube were observed laparoscopically, with what was described as "semi-solid calcified material" from the fallopian tube. Histopathology revealed extensive granulomatous inflammation and Schistosoma haematobium were visualized.

Serological studies were positive. She had a remote history of travel to Egypt and Africa 8 years earlier, where she swum in Lake Malawi.

The second patient presented with acute lower quadrant pain; ultrasound identified two ovarian cysts. A torsed ovary was observed laparoscopically and she underwent a salpingo-oopherectomy. Histopathology revealed ovarian hemorrhage and granulomatous inflammation with giant cells and degenerating schistosomes. Her serology was also positive. She also had a remote history of travel to Africa 8 years earlier, and had swum in Lake Malawi.

Lake Malawi is an especially risky place for a quick swim: estimates suggest the risk of exposure is about 70% with one swim. Infection may remain asymptomatic until years later. Gynecological involvement is one of several presentations of "ectopic" schistosomiasis, although more commonly affects the cervix and vaginal area. However, the schistosomes can readily access the genital venous plexus, and cause upper genital infection, with inflammation and scarring years later. Chronic gynecologic infection may present with fistulae, pelvic pain, dysparunia, and infertility.

HIV and TB treatment: Together?

Source: Havlir DV, et al. Timing of antiretroviral therapy for HIV-1 infection and tuberculosis. NEJM 2011; 365; 16: 1482-1491.

When to initiate antiretroviral therapy (ART) in HIV-infected patients beginning treatment for tuberculosis has been a matter for debate. An open-label, randomized study comparing the benefits of early initiation of antiretroviral therapy (within 2 weeks of initiation of TB medication) versus delayed initiation of ART until 8-12 weeks following initiation of TB medication was conducted. A total of 809 HIV-infected patients with CD4 counts < 250 cells/mm3 with suspected tuberculosis who were beginning antimycobacterial therapy were randomized to either early or late initiation of ART. During the 48 weeks of observation, the risk of newly defined AIDS-related illness or death was similar between the two groups (12.9 vs 16.1% for the early-ART vs later-ART groups, p = 0.45). The most common AIDS-defined illnesses included cryptococcosis, esophageal candidiasis, and Kaposi sarcoma. Overall, 31 deaths occurred in the early-ART group and 37 deaths occurred in the later-ART group; more than half of which were HIV-related and none of which were related to TB infection. However, examination of the data for a prespecified subgroup of patients with CD4 < 50 cells/mm3 demonstrated a statistically significant greater risk of AIDS-related events and/or death in the later ART group compared with the early ART group (26.6% vs 15.5%, p = 0.02). A rationale for delaying initiation of ART has been the associated risk of TB-related immune reconstitution inflammatory sydrome (IRIS) with earlier initiation of ART. Patients in this study were observed to have a significantly lower risk of IRIS in the later ART group compared with the early ART group (5% vs 11%, p < .0001), although the numbers of patients with serious complications of IRIS were similar between the two groups. Prednisone was required to manage nearly half of the patients. Comparing the early vs. late ART groups, IRIS-related symptoms occurred a median of 4.6 and 11.7 weeks following initiation of TB treatment (much earlier in the early HIV treatment group). However, the duration of IRIS symptoms was similar between the two groups (about 69-75 days). Four of the 19 cases of IRIS in the late-ART treatment group occurred before the initiation of ART.

Treatment-related toxicity occurred with a similar frequency between the two groups. And both groups of patients had a similar response to antiretroviral therapy by 48 weeks of study.Slightly more than half (56%) of patients completed their TB treatment without modification or interruption, with no difference observed between the groups.

In conclusion, waiting 8-12 weeks to initiate ART in HIV-positive patients with CD4 counts between 50-250 cells/mm3 who are beginning TB treatment does not appear to significantly increase morbidity or mortality, and is associated with a reduction in IRIS-related events. However, patients with CD4 cells < 50/mm3 are at increased risk for AIDS-related events and mortality and should be started on ART as soon as possible, regardless of the increased risk for IRIS.

Clusters of respiratory illness from HEV68

Source: Centers for Disease Control and Prevention. Clusters of acute respiratory illness associated with human enterovirus 68 – Asia, Europe, and United States, 2008-2010. MMWR, Morb Mortal Wkly Rep 2011;60:1301-1304.

Human enterovirus 68 (HEV68) is one of the many summer-fall picornaviruses, but unlike its enteroviral cousins, seems to almost exclusively cause respiratory illness. Reports identify it as a rare cause of respiratory illness, often occurring in small clusters. This MMWR report documents the recent evidence for HEV68 respiratory infection in the Philippines, Japan, Netherlands and the United States. It identifies HEV68 as a more frequent cause of respiratory illness than previously recognized.

For example, during a clinical study of respiratory illness in pediatric patients hospitalized in the Philippines, specimens from 816 patients were retrospectively screened for HEV68 by RT-PCR. Twenty-one (2.6%) were positive; 17/21 (81%) involved children ages 0-4, and two cases resulted in fatal respiratory infection. In the United States, adults admitted to a hospital in Atlanta with respiratory illness began being screened using a broad-based multi-pathogen testing system that includes entero-rhinovirus. Of 68 specimens testing positive for "ERV", 6 (8.8%) were positive for HEV68. Three of these 6 patients were 50 years or older, two were immunocompromised, five had fever and 4 cough; none of them developed respiratory failure or died. Similarly, at a pediatric hospital in Philadelphia, 390 children treated for respiratory illness were evaluated for HRV. Specimens from 66 subjects were submitted to the CDC for further testing, of which 15 (42%) were positive for HEV68. Half involved children ages 0-4, and 15 required admission to ICU .

Symptoms from HEV68 vary from mild respiratory symptoms to more severe respiratory failure; new-onset asthma, especially in a child may be present. Cases generally occur in late summer-fall. Clinicians should be aware that HEV68 may result in clusters of cases of viral respiratory illness.