Washington, Nov 30 (IANS): Loopholes exist in the new Covid-19 vaccine requirement issued by US Centers for Disease Control and Prevention (CDC) as the guideline fails to cover all potential coronavirus carriers, Forbes has warned.

"The good news: US requires air travellers entering the country to be vaccinated; The crazy news: this rule doesn't apply to US citizens," Forbes quoted a tweet on Saturday by New York City Council member Mark D. Levine as saying.

"The Presidential Proclamation and CDC's Order do not apply to US citizens, US nationals, or US lawful permanent residents (Green Card holders)," the CDC specified on its website, Xinhua news agency reported.

A key to such Covid precautions in general is "uniformity and consistency," Forbes said, "if you are going to rely on a Covid vaccination requirement, apply it equally to everyone" and to show by action that "such decisions are driven by science and not politics or business."

Moreover, with consistency, people would be less inclined to feel that they are being discriminated against or treated unfairly, Forbes said.