Local Coronavirus Update

Picture of corona vaccine

By: T. Jeffersonian

By the end of May 2021, Hawaii state health officials expect to have 1.5 million doses of the vaccine administered. That number translates to roughly 70 percent of the state’s residents 16 and up being fully vaccinated.  The state health department’s goal is to achieve herd immunity.  Herd immunity is achieved when enough people in a population have been vaccinated to break the flow of transmission and make it difficult for someone who’s infected to pass on the disease.  For some time now, Dr. Anthony Fauci has been describing herd immunity as being attained when 70 – 85 percent of the population is vaccinated.  The goal posts are moving slightly.  Now health officials are saying 70 – 90 percent of an entire population, including children, need to be vaccinated.  With more than 900,000 doses of the Coronavirus vaccines administered in Hawaii, health officials describe the state already having some level of herd immunity.  Vaccinations break down the viral transmission chain and prevents hospitalizations and death.  Reaching 70 percent herd immunity at the end of May 2021 will be a big milestone for Hawaii. 

There is still work to be done beyond the end of May 2021 milestone.  Regardless the immunity attained, the virus remains a threat.  15-20 percent more of the state population still requires vaccination beyond the end of May and this will include children under the age of 16 years of age.  Children vaccine trials look very promising so far.  State health officials say the earliest kids can be eligible for the shot is this summer. Until that time, Hawaii needs to get as many of our adults vaccinated as possible and a number of kids vaccinated before state can relax enough to eliminate most of these public health measures such as masking, social distancing, and limited indoor occupancy. 

Coronavirus variants are causing grave concerns requiring continued public vigilance and prolonged health measures but there seems to be some good news ahead.  Researchers have discovered that the chances of getting Coronavirus from surface contacts, like door knobs and toilet seats, are much lower than thought.  Surface contact infections occur about 1-in-10,000 cases.  Existing vaccines are proving effective against some variants such as the United Kingdom and California variants.    Different Coronavirus variants are partially resistant to antibody defenses.  This antibody resistance has spurred renewed interest in other immune responses that protect against viruses.  In particular, scientists are hopeful that T cells — a group of immune cells that can target and destroy virus-infected cells — could provide some immunity to Coronavirus, even if antibodies become less effective at fighting more severe variations.  Researchers are now picking apart available data and running more tests, looking for signs that T cells can help maintain lasting immunity.    Coronavirus vaccine development has largely focused on antibodies, particularly those antibodies that bind to crucial viral proteins and block infection.  Such antibodies can hold the key to sterilizing immunity, which not only reduces the severity of an illness, but prevents infection altogether. Sterilizing immunity is the gold standard, but to reach that standard typically requires large numbers of antibodies which is not necessarily always the case. 

In an infected person, the immune system produces antibodies plus T cells that can also target viruses. Some of these, known as killer T cells, seek out and destroy cells that are already infected with the virus. Others, called helper T cells are important for various immune functions, including stimulating the production of more antibodies and more killer T cells.  T cells will not prevent infection, because they kick into action only after a virus has infiltrated the body; however, they are important for clearing an infection that has already started.  In the case of Coronavirus, killer T cells appear to mean the difference between a mild infection and a severe one that requires hospital treatment.  T cells kill virus-infected cells before they spread from the upper respiratory tract and make Coronavirus more severe. The cells are also thought to reduce transmission by restricting the amount of virus circulating in an infected person, meaning that the person sheds fewer virus particles into the community.  T cells are also believed to be more resistant than antibodies to threats posed by the new emerging Coronavirus variants such as the United Kingdom, California, South African, Brazilian, and Double Mutated Indian variant.   

Initial studies show that infected victims typically generate T cells that target at least 15–20 different fragments of Coronavirus proteins inside the virus.  The protein snippets targeted by T cells can vary widely from person to person, meaning that a population will generate a large variety of T cells that can more effectively snare a virus after infection and prevent it from mutating to escape cell recognition.  Preliminary evidence seems to show that the vast majority of T-cell responses are unlikely to be affected by the mutations that make Coronavirus more resistant to antibodies.  Some coronavirus vaccine developers are already looking at ways to develop next-generation vaccines that stimulate T cells more effectively.  Clinical trials are already underway for an experimental vaccine that incorporates both a genetic code to elicit T-cell responses, as well ensuring that antibody responses are effective.   Though the results are not final, results look very promising.