Study: COVID-19 Nasal Spray Vax Causes Viral Shedding

Simian Practicalist
1 day ago
3 min read

A study by P. Spearman et al titled “Safety and immunogenicity of intranasal parainfluenza virus type 5 (PIV5)–vectored COVID-19 vaccine in adults and teens in an open-label phase 1 trial” posted on 4 July 2025 reckons the nasal spray vaccine CVXGA1 by CyanVac LLC is “potentially effective”. Rah!!!

The paper is about 12 pages. According to the spiel:

As an enveloped negative-strand RNA virus in the family Paramyxoviridae, parainfluenza virus type 5 (PIV5) is not known to cause disease in humans. A PIV5 vector has been extensively studied preclinically for vaccine development against diverse pathogens including Middle East respiratory syndrome coronavirus and Rous sarcoma virus (RSV). CVXGA1 is a vaccine candidate based on this PIV5 vector that encodes the S protein of SARS-CoV-2 from the ancestral WA.1 strain.

I am not a medical professional but one has to wonder about the point of a vaccine in any form when the existing versions are not safe and effective.

Setting that aside for the sake of argument, a case can be generally argued that for a virus in which the respiratory tract is the initial site of infection, a nasal spray may be more fitting and it avoids a needle. That, of course, assumes a vaccine is necessary in the first place for what is basically a cold.

Anyway, even for an early trial, a study sample of 72 participants divided into 4 groups seems too small. Although Group 1 with 16 adults who have not taken any COVID-19 vaccine or had been previously infected, the study lacks an unvaccinated control group. The other three groups had been infected or received an mRNA injection at least 6 months before the trial.

Group 1 received a low dose and the other three groups received a high dose. Group 4 is comprised of adolescents aged 12 to 17 years.

The study period, from September 2021 to May 2023, also seems too short.

Although the adverse events were all reportedly mild, 18 (25%) had a runny nose/nasal congestion, 7 (10%) had a sore throat and 18 (25%) had a headache, amongst other conditions. I personally wouldn’t want a nasal spray vaccine with a 10% chance of getting a sore throat and a 25% chance of a headache.

Generally, it seems Group 1 with the lower dose had a weaker response. But in terms of practical results:

During the period of the trial from September 2021 to May 2023, various waves of SARS-CoV-2 variant infections emerged in the US. Group 1 (enrolled from September 2021 to February 2022) had the highest overall COVID-19 infection rate: 73.3%, graded as mild or moderate on the AE scale. Groups 2 to 4 had lower infection rates: 11.1% for group 2 (enrolled from February 2022 to November 2022), 22.2% for group 3 (enrolled from April 2022 to September 2022), and 11.8% for group 4 (enrolled from September 2022 to January 2023).

At these infection rates, why bother?

In addition, virus shedding was detected in 14 participants (from Groups 2 to 4) on Day 2. Nothing was detected on Day 8. This cannot be dismissed as due to coincidental infection since one participant from Group 3 was excluded from the study after a positive diagnosis on Day 4. This is equivalent to 25% of the high-dose participants.