Differing asthma prevalence by gross national index of country of birth among New York City residents

Number of seasonal exposures to Japanese cedar pollen increases the risk of sensitization: Observational study in Korean adults

Sensitization to seasonal allergens usually requires repeated exposure to them. However, research on the extent of exposure that increases the risk of sensitization to specific allergens is lacking. Therefore, we investigated the levels of exposure to Japanese cedar pollen that increased the risk of sensitization to it. A cross-sectional study was conducted with 857 college students living in Jeju, South Korea, as it is the only province in Korea where Japanese cedar pollen levels are high. Questionnaires about demographic characteristics were distributed and skin prick tests for allergic sensitization were performed. Sensitization rates of groups divided by residence period were 3.8% (less than 1 year), 1.8% (1–2 years), 8.5% (2–3 years), 10.3% (3–4 years), 14.8% (4–10 years), and 19.1% (over 10 years). Residence period was an influencing factor of sensitization rate to Japanese cedar pollen, and the cut-off value of the residence period that increased the risk of sensitization to Japanese cedar pollen was found to be 25 months. Repeated exposure to seasonal allergens was related to an increased sensitization rate in young adults. Our results suggested that exposure to Japanese cedar pollen for over two seasons could increase the risk in Korean adults.

The pertussis hypothesis: Bordetella pertussis colonization in the etiology of asthma and diseases of allergic sensitization

Decades of peer reviewed evidence demonstrate that: 1)Bordetellapertussisand pertussis toxin are potent adjuvants, inducing asthma and allergic sensitization in animal models of human disease, 2)Bordetella pertussisoften colonizes the human nasopharynx, and is well documented in highly pertussis-vaccinated populations and 3) in children, a history of whooping cough increases the risk of asthma and allergic sensitization disease. We build on these observations with six case studies and offer a pertussis-based explanation for the rapid rise in allergic disease in former East Germany following the fall of the Berlin Wall; the current asthma, peanut allergy, and anaphylaxis epidemics in the United States; the correlation between the risk of asthma and gross national income per capita by country; the lower risk of asthma and allergy in children raised on farms; and the reduced risk of atopy with increased family size and later sibling birth order. To organize the evidence for the pertussis hypothesis, we apply the Bradford Hill criteria to the association between Bordetella pertussisand asthma and allergicsensitization disease. We propose that, contrary to conventional wisdom that nasopharyngealBordetella pertussiscolonizing infections are harmless, subclinicalBordetella pertussiscolonization is an important cause of asthma and diseases of allergic sensitization.

Immigrant Respiratory Health: a Diverse Perspective in Environmental Influences on Respiratory Health

PURPOSE OF REVIEW

The aim of this review is to examine the prevalence of and impact of environmental exposures in the workplace and home on immigrant respiratory health in the USA.

RECENT FINDINGS

Few studies report levels of workplace and home environmental exposures for immigrant children and adults, and documenting these findings is an important first step to addressing their respiratory health concerns. Rates of respiratory disease are lowest upon first arrival and increase with duration of residency in the USA. Community Health Workers may be an efficacious intervention to reducing exposures and improving lung health among immigrant populations. Immigrant children and adults have a high risk of occupational and home environmental exposures that can negatively affect their respiratory health. While limited studies exist, more documentation of these exposures and their impact on immigrant person's respiratory health are needed to begin to tackle these disparities.

Asthma prevalence and severity in low-resource communities

PURPOSE OF REVIEW

The prevalence of asthma was thought to be low in most low-income countries, but several reports have indicated this is not always true. This is a narrative review of recent publications on the burden of asthma in low and middle-income countries (LMIC) and underprivileged communities from developed countries.

RECENT FINDINGS

Several studies have reported a low prevalence of asthma is LMIC, but indicate it is increasing. In the last few years, however, many surveys demonstrated this may not always be true. An analysis of the International Study for Asthma and Allergy in Childhood phase III database indicated although the prevalence of asthma among children and adolescents is higher in the developed countries, symptoms of asthma are often more severe in less affluent nations. The rate of uncontrolled asthma is also higher among underprivileged communities of developed countries. Secondary analysis of data generated by the WHO's world health survey performed among adults of 70 countries indicate symptoms of asthma are less frequent in middle-income countries and more frequent in the extremes, low income and high income. This sort of U shaped distribution suggests the disease (or syndrome) comprise more than one major phenotype related to diverse underlying mechanisms. In fact, recent reports show symptoms of asthma among the poor are associated with unhygienic living conditions, which may reduce the risk of atopy but increase the risk of nonatopic wheezing. Urbanization and exposure to air pollution also seem to contribute to an increasing prevalence severity of asthma in LMIC. Access to proper diagnosis and treatment with controller medications for asthma, specially with inhaled corticosteroids is feasible and cost-effective, reduce symptoms, health resource utilization, improves quality of life, and reduce mortality in low-resource settings.

SUMMARY

Prevalence of asthma was thought to be low in low-income countries, but several reports have indicated this is not always true. Under diagnosis, under treatment, exposure to air pollution, and unhygienic living conditions may contribute to a higher frequency and severity of symptoms of asthma among the poor. Proper diagnosis and treatment with controller medications for asthma is feasible and cost-effective in low-resource settings.