Covid 11/1/20 | COVID 19 Information Page

Covid19mathblog.com

Another study of the obvious – proving the statements made numerous times here and the warning made that the home is less likely to be able to ventilate vs. commercial buildings and likely the source of most spreads per gatherings. https://www.cdc.gov/mmwr/volumes/69/wr/mm6944e1.htm

“To assess household transmission, a case-ascertained study was conducted in Nashville, Tennessee, and Marshfield, Wisconsin, commencing in April 2020. In this study, index patients were defined as the first household members with COVID-19–compatible symptoms who received a positive SARS-CoV-2 reverse transcription–polymerase chain reaction (RT-PCR) test result, and who lived with at least one other household member. After enrollment, index patients and household members were trained remotely by study staff members to complete symptom diaries and obtain self-collected specimens, nasal swabs only or nasal swabs and saliva samples, daily for 14 days. For this analysis, specimens from the first 7 days were tested for SARS-CoV-2 using CDC RT-PCR protocols.† A total of 191 enrolled household contacts of 101 index patients reported having no symptoms on the day of the associated index patient’s illness onset, and among these 191 contacts, 102 had SARS-CoV-2 detected in either nasal or saliva specimens during follow-up, for a secondary infection rate of 53% (95% confidence interval [CI] = 46%–60%).”

“Among fourteen households in which the index patient was aged <18 years, the secondary infection rate from index patients aged <12 years was 53% (95% CI = 31%–74%) and from index patients aged 12–17 years was 38% (95% CI = 23%–56%).”

My hypothesis for why 12-17 less than <12 – teenagers coup up in their room ? and they don’t communicate as much to others in household – I know first hand.

“The median index patient age was 32 years (range = 4–76 years; interquartile range [IQR] = 24–48 years); 14 (14%) index patients were aged <18 years, including five aged <12 years and nine aged 12–17 years. Among index patients, 75 (74%) were non-Hispanic White, eight (8%) were non-Hispanic persons of other races, and 18 (18%) were Hispanic or Latino (Table 1). Index patients received testing for SARS-CoV-2 a median of 1 day (IQR = 1–2) after illness onset and were enrolled in the study a median of 4 days (IQR = 2–4) after illness onset.

The median number of household members per bedroom was one (IQR = 0.8–1.3). Seventy (69%) index patients reported spending >4 hours in the same room with one or more household members the day before and 40 (40%) the day after illness onset. Similarly, 40 (40%) of index patients reported sleeping in the same room with one or more household members before illness onset and 30 (30%) after illness onset.

Among all household members, 102 had nasal swabs or saliva specimens in which SARS-CoV-2 was detected by RT-PCR during the first 7 days of follow-up, for a secondary infection rate of 53% (95% CI = 46%–60%) (Table 2). Secondary infection rates based only on nasal swab specimens yielded similar results (47%, 95% CI = 40%–54%). Excluding 54 household members who had SARS-CoV-2 detected in specimens taken at enrollment, the secondary infection rate was 35% (95% CI = 28%–43%).

Forty percent (41 of 102) of infected household members reported symptoms at the time SARS-CoV-2 was first detected by RT-PCR. During 7 days of follow-up, 67% (68 of 102) of infected household members reported symptoms, which began a median of 4 days (IQR = 3–5) after the index patient’s illness onset. The rates of symptomatic and asymptomatic laboratory-confirmed SARS-CoV-2 infection among household members was 36% (95% CI = 29%–43%) and 18% (95% CI = 13%–24%), respectively.”

“An important finding of this study is that fewer than one half of household members with confirmed SARS-CoV-2 infections reported symptoms at the time infection was first detected, and many reported no symptoms throughout 7 days of follow-up, underscoring the potential for transmission from asymptomatic secondary contacts and the importance of quarantine. Persons aware of recent close contact with an infected person, such as a household member, should quarantine in their homes and get tested for SARS-CoV-2”

The optimistic side 47% don’t become infected even though in same household – not bad odds – not good either. No mentioned of ventilation – no mentioned of health of people infected….Once again an important hypothesis made here is that if you are healthy you can handle higher viral loads before getting infected.

If we hold this to be true – then how exactly will lockdowns work IF you have samples of essential employees in the community and you have gatherings – celebrations etc… It did not work for LA it will not likely work for society bounded by social gatherings. Households need to ventilate more IF you cannot completely isolate. They need access to technology to reduce viral load. Those with kids particularly teenagers it would be VERY hard to guarantee they are not going out and hanging out with friends. You extend this to a family gathering and expect EVERYONE to be isolated – this is very small odds in the US type society.

The discussion of no in school person – lead to numerous social media post of gatherings to do school at each other homes – as noted individual home units do not have an economizer – they don’t bring in any fresh air into the HVAC. At least commercial buildings do and would be much more cost effective to modify than individual homes.

England and France are now in lockdown for a month….got to be awful being a nonessential store. https://www.theguardian.com/world/2020/oct/31/boris-johnson-announces-national-lockdown-england-coronavirus

“Unlike the first national lockdown introduced in March, schools, colleges and universities will remain open, as will childcare and early years care.”

“Johnson also announced a ban on overnight stays and outbound international travel, unless the trips are for work, while places of worship will be open for private prayer but not for services. He also confirmed that the Premier League would continue.”

How one enforces will be interesting – https://www.theguardian.com/world/2020/oct/31/what-could-a-national-covid-lockdown-in-england-mean-coronavirus

What can I leave home for?

People can only leave home for the following reasons:

Education.

To go to work unless it can be done from home.

Outdoor exercise either with household members or with one person from another household.

For all medical reasons and appointments.

To escape injury or harm.

To care for the vulnerable or volunteer.

To shop for food and essentials.

To see people in your support bubble.

Children will still be able to move between homes if their parents are separated.

However, people could face fixed penalty notices from police for leaving their home without one of the above excuses.

NO cheating and it should work – but in all honesty to stop people from celebrating anniversaries bday etc….will be super tough – then not visiting the elderly who perhaps are already looking at near death regardless of covid – all round 2020 suck.

Under 1K death – another super confirmation day for the US at 81K