What happened

Shares of coronavirus vaccine makers generally had a good Wednesday on the back of a coming push on additional jabs, plus a notable recommendation boost by a prominent investment bank.

In contrast to the day's dip in the S&P 500 index, Moderna (MRNA -0.58%) stock enjoyed a 1.6% lift, Comirnaty vaccine co-developers Pfizer (PFE 2.40%) and BioNTech (BNTX 0.74%) respectively rose by 0.9% and 2.7%, and perennial underdog Novavax (NVAX 2.06%) gained 2.6%.

Smiling young person showing off vaccine shot bandage on her arm.

Image source: Getty Images.

So what

Various media reports published Wednesday indicate that the U.S. Centers for Disease Control and Prevention (CDC) will push American pharmacies to cease refusing fourth coronavirus vaccine shots for immuno-compromised people.

The CDC will apparently make its request in a scheduled conference call later this week with pharmacy leaders. This follows numerous reports throughout the country of patients being turned away for jab No. 4. The reluctance is somewhat puzzling as the CDC issued guidance last October that such patients should receive the extra primary shot.

Any initiative to get more shots in arms is particularly a boon for the vaccines that have been either approved or authorized in the U.S. The two leaders in this small category are the Pfizer/BioNTech jab and Moderna's mRNA-1273.

Novavax is not on that list, but earlier this month the biotech filed its clinical trial data with the Food and Drug Administration (FDA). This is a key step in applying for the regulator's Emergency Use Authorization (EUA). So authorization for the company's NVX-CoV2373 might be coming soon. 

Now what

At the moment, Moderna, BioNTech, and -- to a lesser extent -- Novavax stocks are more prone to swings in the fortunes of vaccines. This is because all are still heavily dependent on jabs for their business in contrast to large and diversified healthcare juggernaut Pfizer.

That helps explain why a positive analyst note on Moderna is giving that stock a particular lift. On Wednesday, Deutsche Bank analyst Emmanuel Papadakis upgraded his recommendation on the stock to hold from the former sell (although he cut his price target to $175 per share from $200).