How concerned should we be about the delta variant of the coronavirus?
Dr. Anthony Fauci, the nations leading infectious disease expert, recently called the new delta variant of the coronavirus the greatest threat in the U.S. to our attempt to eliminate COVID-19.  The B.1.617.2 variant is considered highly transmissible and is believed to be responsible for about one in every five cases nationally. However, in Michigan, the latest strain only accounts for less than 1% of cases over the last four weeks. Health officials in Michigan said they arent any more concerned about the delta variant than other currently known strains, particularly for the population that is fully vaccinated. For those who havent completed the recommended vaccine dosage, doctors say the strain still presents a risk. Im not very concerned because the vaccines do appear to work against this new strain, said Dr. Dennis Cunningham, an infectious disease specialist for Henry Ford Health System. Unvaccinated people are certainly susceptible to this one and the others out there, so I encourage everyone to get a vaccine.  As of Tuesday, June 22, Michigan had identified the delta variant in 32 COVID-19 cases across eight counties, according to heath department data. The CDC estimates a prevalence of 0.2% in the state. Over the last four weeks, the alpha variant (B.1.1.7) has been found in 90.5% of sequenced positive test results. The remaining four known variants each made up less than 2.5%. The delta strain, which has been labeled a variant of concern by the World Health Organization, was first detected in India and has spread to more than 90 countries. It has the potential to be the dominant strain across the globe because its believed to be more deadly and more transmissible than previous strains, according to the WHO. Ingham County Health Officer Linda Vail said the latest variant isnt anything to get more worked up about than the (alpha) B.1.1.7 variant for the vaccinated population. As long as vaccines are effective against variants, the biggest concern is for the unvaccinated population, she said. Sometimes these variants can become more transmissible, or they might cause more serious illness or maybe have a higher mortality rate. When they come along and we have an unvaccinated population, it can be a concern for them.  Vail noted that a segment of the population feels safe against coronavirus because they believe they have developed natural immunity from a previous infection. However, like the flu or viruses that cause the common cold, those people could still get sick again if a new variant is different enough from a previous infection. If the time comes when the current vaccines are no longer effective against new coronavirus strains, its possible that people will need a booster vaccine, Dr. Cunningham said. But we have to wait a while to find out.  A United Kingdom study analyzed more than 14,000 cases of people infected with the delta variant and found two doses of the Pfizer vaccine to be 88% effective against the variant, and 96% effective against hospitalization from the strain. Health experts think the Moderna vaccine offers similar protection after two shots, while less data is available about the efficacy of the Johnson & Johnson vaccine. As of Tuesday, nearly 56% of Michiganders 12 and older -- or 4.8 million -- had been at least partially vaccinated, and about 51% -- or 4.39 million individuals -- had been fully vaccinated. Vaccine appointments, including walk-ins, are available throughout the state for individuals 12 years and older. For more information, visit the states COVID-19 vaccine website. Read more on MLive:  CDC investigating rare heart inflammation cases in youth post-COVID-19 vaccination  What immunocompromised people need to know about COVID-19 vaccines  Michigan workplace COVID-19 requirements replaced with recommendations  Its nice to see peoples faces: Michiganders getting back to normal after COVID-19 restrictions lifted