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Geography of Los Angeles County, 2014. Legend. Land elevation is indicated by the shading of green with the lightest shade representing the highest elevation. The 24 health districts of LA County are indicated within their boundaries. Long Beach and Pasadena are cities outside LA County’s jurisdiction and have their own health departments. The dots represent urbanization as these are public facilities such as schools, libraries, post offices, bus stations, fire departments, police stations, museums, and hospitals. West Valley, San Fernando, and Antelope Valley districts are considered endemic for coccidioidomycosis based on environmental conditions and history of high case numbers and incidence rates. The high desert area of Antelope Valley continues to have the greatest potential for land development for projects such as housing, agriculture, and solar farms. Map was made by E.R. using ArcGIS 10.1 software.
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Coccidioidomycosis, also known as Valley Fever, is often thought of as an endemic disease of central California exclusive of Los Angeles County. The fungus that causes Valley Fever, Coccidioides spp., grows in previously undisturbed soil of semi-arid and arid environments of certain areas of the Americas. LA County has a few large areas with such e...
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Ongoing large-scale land development for renewable energy projects in the Antelope Valley, located in the Western Mojave Desert, has been blamed for increased fugitive dust emissions and coccidioidomycosis incidence among the general public in recent years. Soil samples were collected at six sites that were destined for solar farm construction and...
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... Marine mammals do not venture far from waters' edge, though they range considerably north and south off California's shoreline. Infection is assumed to have occurred when cocci arthroconidia came to them on currents of air, possibly from the Mojave Desert (Hector et al. 2011;Thompson III et al. 2015;Guevara et al. 2015;Grayzel et al. 2017). Pacific Ocean marine mammals are often exposed to windblown dust from points well inland. ...
Risks associated with dust hazards are often underappreciated, a gap between the knowledge pool and public awareness that can be costly for impacted communities. This study reviews the emission sources and chemical, physical, and biological characteristics of airborne soil particles (dust) and their effects on human and environmental health and safety in the Pan‐American region. American dust originates from both local sources (western United States, northern Mexico, Peru, Bolivia, Chile, and Argentina) and long‐range transport from Africa and Asia. Dust properties, as well as the trends and interactions with criteria air pollutants, are summarized. Human exposure to dust is associated with adverse health effects, including asthma, allergies, fungal infections, and premature death. In the Americas, a well‐documented and striking effect of soil dust is its association with Coccidioidomycosis, commonly known as Valley fever, an infection caused by inhalation of soil‐dwelling fungi unique to this region. Besides human health, dust affects environmental health through nutrients that increase phytoplankton biomass, contaminants that diminish water supply and affect food (crops/fruits/vegetables and ready‐to‐eat meat), spread crop and marine pathogens, cause Valley fever among domestic and wild animals, transport heavy metals, radionuclides and microplastics, and reduce solar and wind power generation. Dust is also a safety hazard to road transportation and aviation, in the southwestern US where blowing dust is one of the deadliest weather hazards. To mitigate the harmful effects, coordinated regional and international efforts are needed to enhance dust observations and prediction capabilities, soil conservation measures, and Valley fever and other disease surveillance.
... Marine mammals do not venture far from waters' edge, though they range considerably north and south off California's shoreline. Infection is assumed to have occurred when these animals met with airborne Coccidioides arthroconidia, possibly from the Mojave Desert (Hector et al., 2011;Thompson III et al., 2015;Guevara et al., 2015;Grayzel et al., 2017). Pacific Ocean marine mammals are often exposed to windblown dust from points well inland. ...
Risks associated with dust hazards are often underappreciated, a gap between the knowledge pool and public awareness that can be costly for impacted communities. This study reviews the emission sources and chemical, physical, and biological characteristics of airborne soil particles (dust) and their effects on human and environmental health and safety in the Pan-American region. American dust originates from both local sources (western United States, northern Mexico, Peru, Bolivia, Chile, and Argentina) and long-range transport from Africa and Asia. Dust properties, as well as the trends and interactions with criteria air pollutants, are summarized. Human exposure to dust is associated with adverse health effects, including asthma, allergies, fungal infections, and premature death. In the Americas, a well-documented and striking effect of soil dust is its association with Coccidioidomycosis, commonly known as Valley fever, an infection caused by inhalation of soil-dwelling fungi unique to this region. Besides human health, dust affects environmental health through nutrients that increase phytoplankton biomass, contaminants that diminish water supply and affect food (crops/fruits/vegetables and ready-to-eat meat), spread crop and marine pathogens, cause Valley fever among domestic and wild animals, transport heavy metals, radionuclides and microplastics, and reduce solar and wind power generation. Dust is also a safety hazard to road transportation and aviation, in the southwestern US where blowing dust is one of the deadliest weather hazards. To mitigate the harmful effects, coordinated regional and international efforts are needed to enhance dust observations and prediction capabilities, soil conservation measures, and Valley fever and other disease surveillance.
... In addition, geography and regional exposure to dust might have influenced coccidioidomycosis rates in different racial and ethnic groups. Such a hypothesis was explored in coccidioidomycosis surveillance in California (1973 to 2011) that showed the increase in the incidence of coccidioidomycosis followed different environmental exposures, including occupational exposures such as construction and agriculture, regardless of the population's racial and ethnic groups [139]. Such geographically related trends can vary based on regional analysis, as the Hispanic population had a much higher incidence than white populations in areas such as San Joaquin Valley [140], which may be associated with the type of occupation and outdoor recreational activities among different racial and ethnic groups. ...
Racial and ethnic identities, largely understood as social rather than biologic constructs, may impact risk for acquiring infectious diseases, including fungal infections. Risk factors may include genetic and immunologic differences such as aberrations in host immune response, host polymorphisms, and epigenomic factors stemming from environmental exposures and underlying social determinants of health. In addition, certain racial and ethnic groups may be predisposed to diseases that increase risk for fungal infections, as well as disparities in healthcare access and health insurance. In this review, we analyzed racial and ethnic identities as risk factors for acquiring fungal infections, as well as race and ethnicity as they relate to risk for severe disease from fungal infections. Risk factors for invasive mold infections such as aspergillosis largely appear related to environmental differences and underlying social determinants of health, although immunologic aberrations and genetic polymorphisms may contribute in some circumstances. Although black and African American individuals appear to be at high risk for superficial and invasive Candida infections and cryptococcosis, the reasons for this are unclear and may be related to underling social determinants of health, disparities in access to healthcare, and other socioeconomic disparities. Risk factors for all the endemic fungi are likely largely related to underlying social determinants of health, socioeconomic, and health disparities, although immunologic mechanisms likely play a role as well, particularly in disseminated coccidioidomycosis.
... Many of the incoming residents are likely immunologically naïve to coccidioidomycosis. Across several endemic regions, desert land was converted to urban and suburban centers to accommodate population influx, resulting in substantial soil disturbance and potential exposure [35,36]. ...
Coccidioidomycosis is a fungal infection caused by Coccidioides immitis and Coccidioides posadasii. The dimorphic fungi live in the soils of arid and semi-arid regions of the western United States, as well as parts of Mexico, Central America, and South America. Incidence of disease has risen consistently in recent years, and the geographic distribution of Coccidioides spp. appears to be expanding beyond previously known areas of endemicity. Climate factors are predicted to further extend the range of environments suitable for the growth and dispersal of Coccidioides species. Most infections are asymptomatic, though a small proportion result in severe or life-threatening forms of disease. Primary pulmonary coccidioidomycosis is commonly mistaken for community-acquired pneumonia, often leading to inappropriate antibacterial treatment and unnecessary healthcare costs. Diagnosis of coccidioidomycosis is challenging and often relies on clinician suspicion to pursue laboratory testing. Advancements in diagnostic tools and antifungal therapy developments seek to improve the early detection and effective management of infection. This review will highlight recent updates and summarize the current understanding of the epidemiology, diagnosis, and treatment of coccidioidomycosis.
... Inclement weather, such as dust storms (haboobs), has been proposed to increase the risk of infection by Coccidioides (22,23). Although recent analysis shows no such connection (16), we still expect wind speed may be important for explaining human disease because of the dispersal of spores that establish infection (16,17,24,25). Moreover, we hypothesize that the concentration of inhalable particulate matter, quantified as PM10, is important because infectious spores could be dispersed via dust. ...
Coccidioidomycosis (Valley fever) is a disease caused by the fungal pathogens Coccidioides immitis and Coccidioides posadasii that are endemic to the southwestern United States and parts of Mexico and South America. Throughout the range where the pathogens are endemic, there are seasonal patterns of infection rates that are associated with certain climatic variables. Previous studies that looked at annual and monthly relationships of coccidioidomycosis and climate suggest that infection numbers are linked with precipitation and temperature fluctuations; however, these analytic methods may miss important nonlinear, nonmonotonic seasonal relationships between the response (Valley fever cases) and explanatory variables (climate) influencing disease outbreaks. To improve our current knowledge and to retest relationships, we used case data from three counties of high endemicity in southern Arizona paired with climate data to construct a generalized additive statistical model that explores which meteorological parameters are most useful in predicting Valley fever incidence throughout the year. We then use our model to forecast the pattern of Valley fever cases by month. Our model shows that maximum monthly temperature, average PM10, and total precipitation 1 month prior to reported cases (lagged model) were all significant in predicting Valley fever cases. Our model fits Valley fever case data in the region of endemicity of southern Arizona and captures the seasonal relationships that predict when the public is at higher risk of being infected. This study builds on and retests relationships described by previous studies regarding climate variables that are important for predicting risk of infection and understanding this fungal pathogen.
... Soil disturbance in the Mojave Desert often results from recreational off-road dirt biking and from minor agricultural activities around larger cities, such as Lancaster and Palmdale in the western Mojave. In contrast, in the San Joaquin Valley, where NAS Lemoore is located, the natural landscape has changed to industrial agriculture, resulting in only few remaining semi-pristine habitats [65]. Nevertheless, substantial swaths of area are severely eroded near NAS Lemoore, and are covered with invasive grasses or no vegetation with occasional brush. ...
... Incidence of coccidioidomycosis is high in this area. Windblown dust emissions generally occur during periods of high westerly wind, which are common and probably are what have led to an increase in coccidioidomycosis in humans over the last decade during times of increased soil disturbance [65,66]. Prior research in this area by our group has confirmed the presence of DNA of the pathogen in soil and dust [66]. ...
... Incidence of coccidioidomycosis is comparatively low in this rather undisturbed environment. dust emissions generally occur during periods of high westerly wind, which are common and probably are what have led to an increase in coccidioidomycosis in humans over the last decade during times of increased soil disturbance [65,66]. Prior research in this area by our group has confirmed the presence of DNA of the pathogen in soil and dust [66]. ...
Coccidioidomycosis, also known as Valley fever, has been reported among military personnel in Coccidioides-endemic areas of the southwestern United States since World War II. In this study, the prevalence of Coccidioides was confirmed in different soil and dust samples collected near three military bases in California using DNA extraction and Polymerase Chain Reaction (PCR) methods. Analyses of physical and chemical parameters revealed no significant differences between Coccidioides-positive and -negative sites. Soil samples collected in the Mojave Desert (near Twentynine Palms MCAGCC) showed the highest percentage of Coccidioides-positive soil and dust samples. Samples from the San Joaquin Valley (near NAS Lemoore) showed the lowest percentage of positive samples and were restricted to remnants of semi-natural areas between agricultural fields. Our results suggest that soil disturbance around all three military bases investigated poses a potential Coccidioides exposure risk for military personnel and the public. We conclude that once lands have been severely disturbed from their original state, they become less suitable for Coccidioides growth. We propose a conceptual framework for understanding exposure where disturbance of soils that exhibit natural or remnants of native vegetation (Creosote and Salt Bush) generate a high risk of exposure to the pathogen, likely during dry periods. In contrast, Coccidioides-positive sites, when undisturbed, will not pose a high risk of exposure.
... The recent surge (from about 2010 to now) in land development in the California deserts for utility-scale solar energy development (USSED), in addition to fallow farmland resulting from a long-term drought, has contributed to an increase in fugitive dust and coccidioidomycosis in highly endemic areas of the pathogen in the Mojave Desert (Hector et al. 2011;Thompson III et al. 2015;Guevara et al. 2015;Grayzel et al. 2017). Recent studies in the western Mojave Desert, located north of the San Gabriel Mountains that separates the Los Angeles Basin from the Mojave Desert, revealed the presence of C. immitis in 29% of all soil samples collected from disturbed and non-disturbed soils at sites destined for large-scale renewable energy projects west of Lancaster, California (Etyemezian et al. 2018). ...
Coccidioidomycosis, also known as Valley Fever, infects marine mammals along the coast of California. These animals reside far from the Central Valley of California and the Mojave Desert where the fungal pathogen Coccidioides immitis is endemic. An agar gel immunodiffusion (AGID) assay established to screen for coccidioidomycosis exposure in humans and canines was used on blood sera collected from 136 stranded California Sea Lions (Zalophus californianus) of all age groups and 17 Northern Fur Seals (Callorhinus ursinus) between 2013 and 2015, to quantify the prevalence of exposure to the pathogen. We detected Coccidioides-specific antibodies in approximately 11% of California Sea Lions and 24% of Northern Fur Seal pups that were diagnosed with respiratory problems at time of admission to two marine mammal care centers. No significant difference was detected in risk of exposure to the pathogen when comparing sex, or stranding location of California Sea Lions, however, we found that yearlings of California Sea Lions did not show any evidence of seroconversion. Our results confirm that exposure to Coccidioides occurs among pinnipeds, likely due to strong Santa Ana winds, which carry dust from mainland California to the Pacific Ocean. Thus, disease resulting from infection with Coccidioides should be considered as a possible cause for stranding in pinnipeds. The risk of exposure to the pathogen can be considered equal for California Sea Lions, Northern Fur Seals, and other marine mammals that spend significant time in an area affected by mainland dust. The location of greatest exposure is difficult to determine, however, because of sea lion migration behavior and variable wind and weather patterns. The findings of this study have implications for marine mammal rehabilitation and conservation, and also for public health.
... However, this pattern could be changing, because outbreaks could develop in the general population, in addition to more sporadic cases. As California land becomes more arid, precipitation patterns become less predictable, the state becomes more populous, and the cost of living continues to increase, more people who have never come in contact with Coccidioides are relocating to dry or desert areas, increasing the potential for contact with the fungus, which is endemic to arid regions in the state (20,21). Moreover, California health departments have begun to link wildfires, which are expected to occur more frequently as climate changes, with developing coccidioidomycosis among firefighters and others in more populated and endemic Central Coast counties (22,23). ...
... In another Los Angeles study, a shift in coccidioidomycosis infection in the area was indicated. Compared with 2000 through 2003, 19 of 24 health districts in the county had a 100%-1,500% increase in overall cases during 2008-2011 (21). In addition to high rates of infection among workers associated with construction, which has been found or suggested in other studies (14,47), the authors found increased risk associated with outdoor recreational activities (OR = 1.75, 95% CI: 1.23, 2.48). ...
... In addition to high rates of infection among workers associated with construction, which has been found or suggested in other studies (14,47), the authors found increased risk associated with outdoor recreational activities (OR = 1.75, 95% CI: 1.23, 2.48). They also found elevated risk among the elderly (age >65 years) and those younger than 25 years (21). It should be noted that some areas of Los Angeles were previously not known to host Coccidioides, suggesting coccidioidomycosis infection may emerge in other unknown areas of California as populations shift. ...
California has seen a surge in coccidioidomycosis (Valley fever), a disease spread by the Coccidioides Immitis fungus found in soil throughout the state, particularly in the San Joaquin Valley. In this paper, we reviewed epidemiologic studies examining outbreak and sporadic cases of coccidioidomycosis and considered their possible relationship to environmental conditions, particularly the state's growing aridity, drought and wildfire conditions. Most of the studies we reviewed pertained to cases occupationally-acquired in construction, military, archeological and correctional institutional settings where workers faced exposure to dust in Coccidioides Immitis-endemic areas. A few reviewed outbreaks in the general population related to dust exposure from natural disasters, including an earthquake-associated landslide and a dust storm that carried particles long distances from endemic areas. Although many of California's coccidioidomycosis outbreaks have been occupationally-related, changing demographics and new, immunologically-naive populations in dry, endemic areas could expose the general population to Coccidioides Immitis spores. Given the high rate of infection among largely healthy workers, the general population, comprised of some elderly and immunocompromised individuals, could face additional risk. With climate-related events like drought and wildfires also increasing in endemic areas, future research is needed to address the possible associations between these phenomena and coccidioidomycosis outbreaks.
... It is important to remember that the endemic areas include the urban areas of Phoenix, Tucson, Los Angeles, and San Diego, so one does not have to travel to the open desert to contract coccidioidomycosis. Although urbanization probably reduces the risk of infection by decreasing the surface area of exposed contaminated soil, it also increases the numbers of people who can potentially be infected by airborne arthroconidia that are generated by activities that disturb soil, such as construction and earthquakes [19,20]. In addition, windborne spores from an endemic area can infect people and animals many miles from the endemic area [21]. ...
Coccidioides immitis and C. posadasii are two highly pathogenic dimorphic fungal species that are endemic in the arid areas of the new world, including the region from west Texas to southern and central California in the USA that cause coccidioidomycosis (also known as Valley Fever). In highly endemic regions such as southern Arizona, up to 50% of long term residents have been infected. New information about fungal population genetics, ecology, epidemiology, and host-pathogen interactions is becoming available. However, our understanding of some aspects of coccidioidomycosis is still incomplete, including the extent of genetic variability of the fungus, the genes involved in virulence, and how the changes in gene expression during the organism’s dimorphic life cycle are related to the transformation from a free-living mold to a parasitic spherule. Unfortunately, efforts to develop an effective subunit vaccine have not yet been productive, although two potential live fungus vaccines have been developed.
... Children with primary lung infection mainly may have fever, malaise, and chest pain, but it could affect bone and skin tissue, meninges and lymph nodes. In endemic areas, cough, fever, and cervical adenopathies are a useful triad for diagnosis [10] [11]. ...
