Hurricane María drives increased indoor proliferation of filamentous fungi in San Juan, Puerto Rico: a two-year culture-based approach

Abstract

Extensive flooding caused by Hurricane María in Puerto Rico (PR) created favorable conditions for indoor growth of filamentous fungi. These conditions represent a public health concern as contamination by environmental fungi is associated with a higher prevalence of inflammatory respiratory conditions. This work compares culturable fungal spore communities present in homes that sustained water damage after Hurricane María to those present in dry, non-flooded homes. We collected air samples from 50 houses in a neighborhood in San Juan, PR, 12 and 22 months after Hurricane María. Self-reported data was used to classify the homes as flooded, water-damage or dry non-flooded. Fungi abundances, composition and diversity were analyzed by culturing on two media. Our results showed no significant differences in indoor fungal concentrations (CFU/m3) one year after the Hurricane in both culture media studied (MEA and G25N). During the second sampling period fungal levels were 2.7 times higher in previously flooded homes (Median = 758) when compared to dry homes (Median = 283), (p-value < 0.005). Fungal profiles showed enrichment of Aspergillus species inside flooded homes compared to outdoor samples during the first sampling period (FDR-adjusted p-value = 0.05). In contrast, 22 months after the storm, indoor fungal composition consisted primarily of non-sporulated fungi, most likely basidiospores, which are characteristic of the outdoor air in PR. Together, this data highlights that homes that suffered water damage not only have higher indoor proliferation of filamentous fungi, but their indoor fungal populations change over time following the Hurricane. Ultimately, after nearly two years, indoor and outdoor fungal communities converged in this sample of naturally ventilated homes.

Wake-up Call: Rapid Increase in Human Fungal Diseases under Climate Change

“…Wound contamination and exposure to mold in housing are two potential sources of post-disaster fungal infection, according to Hoenigl. Extensive flooding caused by Hurricane Maria in Puerto Rico 36 and Hurricane Harvey in Texas, 37 both in 2017, was linked to increases in invasive mold infections post-hurricane. 36 , 37 …”

“…Extensive flooding caused by Hurricane Maria in Puerto Rico 36 and Hurricane Harvey in Texas, 37 both in 2017, was linked to increases in invasive mold infections post-hurricane. 36 , 37 …”

Influence of climate change on emerging pathogens and human immunity

“…22 After Hurricane María of 2017, water-damaged households in Puerto Rico showed the growth of filamentous fungi, including Aspergillus spp. 23 Molds rising within humid or water-damaged households is occasionally accompanied by a higher risk of asthma in kids and grownups. Humans getting ill due to increased exposure to fungal toxins is a phenomenon known as "sick building syndrome".…”

Disaster Microbiology—a New Field of Study

“…Filamentous fungi, including Aspergillus spp. also proliferated within water-damaged homes in Puerto Rico following Hurricane María ( 16 ). Molds growing within damp or water-damaged homes is sometimes associated with increased risk of asthma in children and adults ( 17 ).…”