† A COVID-19 case in a fully vaccinated person occurred when SARS-CoV-2 RNA or antigen was detected in a respiratory specimen collected ≥14 days after completing the primary series of a COVID-19 vaccine with Food and Drug Administration (FDA) approval or emergency use authorization. The COVID-19 case definition, including criteria to distinguish a new case from an existing case, is per the July 2021 update to the national standardized surveillance case definition and national notification for 2019 novel coronavirus disease (COVID-19) (21-ID-01) (https://ndc.services.cdc.gov/case-definitions/ coronavirus-disease-2019-2021/). Fully vaccinated persons were those with a completed primary series of 2 doses of the Pfizer-BioNTech or Moderna mRNA vaccine or a single dose of the Janssen vaccine (https://www.cdc.gov/ coronavirus/2019-ncov/vaccines/stay-up-to-date.html). A COVID-19 case in an unvaccinated person occurred when the person did not receive any FDAauthorized COVID-19 vaccine doses before the specimen collection date. Cases were excluded in partially vaccinated persons who received at least one FDAauthorized or approved vaccine dose but did not complete a primary series ≥14 days before collection of a respiratory specimen with SARS-CoV-2 RNA or antigen detected. Ascertaining vaccination status for COVID-19 patients through active linkage of case surveillance and immunization information systems typically assumes that cases among persons who are unmatched to the registry are unvaccinated. This analysis represents the combined impact of the Pfizer-BioNTech, Moderna, and Janssen COVID-19 vaccines, which had different clinical efficacies against confirmed infection. Information on different FDA-authorized and approved COVID-19 vaccine products, including clinical efficacy, is available online. https://www.cdc.gov/coronavirus/2019-ncov/ vaccines/different-vaccines.html
Purpose
Birds are implicated in spoiling and decay of buildings, especially through their droppings. Pigeons are considered the main culprits, and several studies have examined the effects and chemistry of accumulations of droppings without evidence to the exact origins of the source of the excreta. The paper aims to discuss these issues.
Design/methodology/approach
This study reviews and summarises the state of knowledge with regard to the impact of bird excreta on buildings. It experimentally assesses the acidity of fresh pigeon excreta with different diets and examines the development of the acidity of the excreta after voiding.
Findings
Feral pigeons in urban settings are known to be fed by a range of foods. Urban food scraps-derived diets produce more acidic excreta than more natural diets such as seeds. This is a first study of its kind to examine the impact of a bird’s diet on the pH and thus the resulting (potential) decay of masonry.
Research limitations/implications
This study showed that from a management’s perspective, pigeons that subsist entirely on human provided foods will be depositing more initially acidic faeces. If faecal accumulation occurs; then, mould and other bacteria quickly alter the chemistry from acidic towards basic, but the damage may already be done.
Originality/value
This paper is the first study of its kind to examine the effects of fresh pigeon droppings of known origin and age once voided from the intestine. This allows the authors to assess the impact during the first few days.
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