The new NextSeq 550 sequencing machine at UCSF's clinical lab on Berry Street looks like a microwave with a computer keyboard, but to microbiologist Charles Chiu, it is the key to California's fight against the deadliest, most invasive virus to strike humanity in decades. The professor of medicine at UCSF will be using the black contraption ... to sequence the genomes of the viruses infecting hundreds of COVID-19 patients in the Bay Area during the next few weeks. Chiu ... is one of the top infectious disease specialists in the world. He has assembled an expert team of scientists ... to find critical clues about where the viral outbreaks in the Bay Area came from and how quickly the disease is spreading. He has already analyzed nine samples from the more than two dozen passengers who tested positive for the coronavirus on the Grand Princess cruise ship and is close to pinpointing the origin of those cases. Those sequences belong in the same cluster as the infection in Washington state," Chiu said. "They really suggest a link between Washington state and California." Chiu said tracking the spread of the virus through genetics is possible because coronaviruses are known to have one to two mutations per month, allowing genomic sequencing to track a particular strain back to its origin. The rate of mutation in coronaviruses is much slower than it is with the influenza virus, which averages about eight to 10 mutations per month.