He says the Pfizer, Moderna, and Johnson and Johnson vaccines are still the most effective way to protect yourself from suffering serious illness, as cases rise in the Quad Cities and across the country
"Our population rates have now gone beyond what we saw in March and April last spring and look like they're continuing on the way up. So we're over 40 cases per 100,000 (population) per day, 14-day moving average."
In addition, he recommends masks and social distancing to prevent the spread of the coronavirus.
Katz says booster shots are recommended for those who received the Pfizer vaccine, and are 65 and older or living in long-term care facilities, and for ages 50 to 64 with high-risk medical conditions.
"Very modest but good data that there's been a very mild downward shift in the efficacy of the Pfizer vaccine preventing severe illness in those groups."
He says the data on COVID-19 is changing every day, and these and other recommendations will probably change in the coming weeks and months.
Both Rock Island County and Scott County health departments offer walk-in vaccinations, and they're also available from many local pharmacies.