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Richard Lampman

Publications and source records attributed to Richard Lampman.

8 recordsLinked to original sources
PubMed2006

Spatio-temporal analyses of West Nile virus transmission in Culex mosquitoes in northern Illinois, USA, 2004.

After a severe outbreak of West Nile virus (WNV) in Cook County, Illinois, in 2002, detections of WNV in mosquitoes were frequent across the state in the following years despite small numbers of human cases. We conducted a spatio-temporal analysis of Culex (subgenus Culex) mosquitoes collected in 2004 in three mosquito abatement districts (MAD) in Cook County by calculating monthly estimates of mosquito density, prevalence of infected mosquitoes, and exposure intensity, which in turn is a product of mosquito density and infection rates. Mosquito infections were detected early at three sites in late May and were widely detected throughout the three MADs in the summer with infection rates as high as 13 per 1000 in August. Exposure intensities were higher at sites adjacent to the Des Plaines River, especially in August and September. The aggregated pattern of WNV transmission along the river might be related to the existence of substantial forest preserves and wetlands that might produce ecological conditions favorable for mosquito proliferation and interactions between mosquitoes and birds.

Animals↗
PubMed2006

Culex population dynamics and West Nile virus transmission in east-central Illinois.

Temporal changes in the abundance Culex restuans and Culex pipiens were monitored in east-central Illinois for over a decade using infusion-baited oviposition traps. The 2 species typically exhibited a seasonal shift in relative abundance with a mean crossover date (when the proportion of egg rafts from both species is equal) of August 10 or 11, depending on leap year, with a 95% confidence interval of +/- 10.7 days. The date of crossover was linearly related to the date of last spring frost and occurred on average about 123 days after the last spring frost. Despite the predictability of crossover, the weekly pattern in the proportion of Cx. pipiens before and after crossover varied considerably, even between years with similar crossover dates. After West Nile virus became established in our area, we found that transmission based on Culex from gravid traps did not increase until Cx. pipiens abundance increased in oviposition traps. Infection rates peaked within the half-month period after crossover. The peak in Cx. pipiens abundance in oviposition traps during this 3-year period was between the 2nd half of August and the end of September. A higher magnitude of transmission in 2002 coincided with warmer temperatures during July and August and an extended period in which the 2 Culex species were in relatively equal abundance.

Animals↗
PubMed2006

Does the roosting behavior of birds affect transmission dynamics of West Nile virus?

The potential role of many urban passerine birds in the transmission of West Nile virus (WNV) is well-documented by studies on host competency, seroprevalence in wild birds, and identification of vector blood meal source. In contrast, the impact of bird behavior on transmission dynamics is largely unexplored. Bird roosting (perching) behavior may be a critical component regulating WNV transmission because of the crepuscular/nocturnal feeding behavior of Culex mosquitoes, the primary vectors of WNV. We used radio telemetry to determine the roosting behavior of American crows (Corvus brachyrhynchos) and northern cardinals (Cardinalus cardinalus). On average, healthy crows moved slightly shorter distances between roosts than viremic crows, 1,038.3 meters versus 1,255.5 meters, while cardinals only moved 54.7 meters. Given the average movements of crows and cardinals between roosts, crows, which are viremic for five days, could spread the virus throughout a mean +/- SE area of 20.84 +/- 0.79 km(2), while viremic cardinals would, on average, only spread the virus over a mean +/- SE area of 0.03 +/- 0.01 km(2). Because the crow population in Illinois is decreasing at a rate of 11.5% per year and up to 35.6% per year in certain locations, crows are becoming scarce in some areas, thus reducing their role as wild bird sentinels. We suggest that if crows are important in dispersing WNV, large decreases in their abundance will shift transmission cycles to a more focal nature because of the differences in roosting behavior of crows compared with other urban birds, such as cardinals.

Animals↗
PubMed2005

The emergence of west nile virus during a large outbreak in Illinois in 2002.

In 2002, the world's largest outbreak of neuroinvasive West Nile virus (WNV) disease occurred. Illinois reported 21% of the total cases in the United States, the most among all states. The epidemiology of WNV in Illinois in 2002 was examined to determine factors associated with severe disease and death. A total of 884 cases were identified and there were 66 deaths. The overall attack rate of WNV infection was 7.1 per 100,000 population and this increased with age. The median ages of patients and patients who died were 56 and 78 years, respectively. Among patients who died, 91% were diagnosed with encephalitis and the case-fatality rate for patients with encephalitis was 18.6%. Patients more than 50 years old had a significantly higher risk of being reported with encephalitis (relative risk [RR] = 3.3, 95% confidence interval [CI] = 2.6-4.3%) and death (RR = 22.3, 95% CI = 5.5-90.4%). Clinicians evaluating elderly patients with WNV infection should assess patients closely for progression of disease.

Adolescent↗
PubMed2003

Pericardiocentesis with extended catheter drainage: an effective therapy.

BACKGROUND: The most effective method for managing pericardial effusions has yet to be identified. This study evaluates the efficacy and safety of echocardiographic-guided placement of indwelling catheters into the pericardial space. METHODS: This study consists of a 5-year retrospective chart review of consecutive patients coded with benign or malignant pericardial effusions who presented for drainage procedures to a single surgeon at a 260-bed hospital. Complication, recurrence, and survival rates were studied. RESULTS: Between January 1996 and August 2001, a total of 29 pericardial drainage procedures were performed; eight of those also underwent talc sclerosis. Mean follow-up was 16 months. Three patients (10%) required conversion to thoracotomy; of those remaining, 25 of the 26 procedures were performed under local anesthesia with intravenous sedation. The identified etiologies for pericardial effusions were malignancy (76%), idiopathic (14%), postcoronary artery bypass grafting procedure (3%), viral pericarditis (3%), and uremia (3%). Echocardiographic features of tamponade were documented in 72%. Mean +/- SEM length of postprocedure in-hospital stay was 6.7 +/- 0.82 days. The overall complication rate was 10% (pneumothorax and cardiac injury). Recurrence rate within 30 days was 7%. Thirty-day mortality was 21%, and more than 90-day survival was 72%. CONCLUSIONS: Pericardiocentesis with extended catheter drainage is a safe treatment for management of clinically significant, malignant and benign, pericardial effusions and can be performed effectively under local anesthesia with intravenous sedation.

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