32-06: Common Viral Respiratory Infections

Key Clinical Updates in Common Viral Respiratory Infections

CMDT regularly updates the ever-evolving knowledge of SARS-CoV-2 in Chapter 32-06. See related manifestations throughout the text, including Chapter 10-42: Infectious Myocarditis, Chapter 14-12: Primary VTE Prevention & Treatment in Severe COVID-19, and Chapter 22-10: COVID-19 & the Kidney.

August 15, 2022 Updates

• The omicron variant continues to evolve with increasing neutralization escape. BA.2.12.1, BA.4, and BA.5 subvariants substantially escape neutralizing antibodies induced by both vaccination and infection. Neutralizing antibody titers against the BA.4, BA.5, and BA.2.12.1 subvariants were lower than titers against the BA.1 and BA.2 subvariants. Hachmann NP et al. N Engl J Med. 2022;387:387. [PMIDs: 35731894] Wang Q et al. Nature. 2022 Jul 5. [Epub ahead of print] [PMID: 35790190] https://covid.cdc.gov/covid-data-tracker/#variant-proportions

• More than one-third of US high school students reported poor mental health during the COVID pandemic, and almost half said they had felt persistently sad or hopeless during the past year. Jones SE et al. MMWR Suppl. 2022;71:16. [PMID: 35358165]

• COVID-19 has been associated with increased risk of herpes zoster virus (VZV) reactivation (“shingles”) in adults 50 years and older. Bhavsar A et al. Open Forum Infect Dis. 2022;9:ofac118. [PMID: 35392454]

• Among the monoclonal antibodies authorized for clinical use, only bebtelovimab retains full potency against both BA.2.12.1, BA.4, and BA.5 Wang Q et al. Nature. 2022 Jul 5. [Epub ahead of print] [PMID: 35790190]

• In the United States, on August 11, 2022, the CDC issued an update of their recommendations, including for isolation after exposure, isolation when infected, and asymptomatic testing. The CDC update included the statement “This guidance acknowledges that the pandemic is not over, but also helps us move to a point where COVID-19 no longer severely disrupts our daily lives.” https://www.cdc.gov/media/releases/2022/p0811-covid-guidance.html

• Several studies indicate that breakthrough infections are reduced by receiving a fourth mRNA vaccine dose. One Israeli study of nearly 30,000 health care workers found that overall breakthrough infection rates were 368 of 5331 (7%) in the four-dose group and 4802 of 24,280 (20%) in the three-dose group (relative risk, 0.35; 95% CI, 0.32–0.39). Cohen MJ et al. JAMA Netw Open. 2022;5:e2224657. [PMID: 35917125]

• A SARS-CoV-2 omicron component (specifically, an omicron BA.4/5 Spike protein component) will be included in COVID-19 vaccines used for boosters in the United States beginning in fall 2022.

• The FDA granted an EUA for use of the Novavax COVID-19 vaccine in individuals 18 years of age and older. This vaccine contains the SARS-CoV-2 Spike protein and Matrix-M adjuvant and requires two doses, 3 weeks apart. https://www.cdc.gov/mmwr/volumes/71/wr/mm7131a2.htm?s_cid=mm7131a2_w

ESSENTIALS OF DIAGNOSIS

• When symptomatic, adults often have respiratory tract illness with fever and cough, upper tract symptoms being more prominent with the omicron variant.

• Advanced pulmonary complications (pneumonia, acute respiratory distress syndrome [ARDS]) occur with fulminant disease.

• High predilection for older adults, patients who are immunocompromised, have chronic diseases, who live in crowded conditions.