Liberia reports another case of Ebola virus infection...

Reset the contacts clocks. Liberia has had a second setback in the fight to rid West Africa of human Ebola virus (EBOV) infections. 

While we were academically aware this could happen again, I'd venture to say we probably thought the next case of Ebola virus disease (EVD) would return to Sierra Leon or Guinea. Liberia which was declared free of known transmission back in 03-SEPT-2015...78-days or 2-months and 17-days ago, and was without a case for 42 days before that.

This was where I learned about the new case from...

Looks like new case of #Ebola here in #Liberia. I'm confident that the Govt will again contain it effectively. Hope the poor boy recovers.

— Sinead Walsh (@SWalshIRL) November 20, 2015

It has now been confirmed that a 15-year old male, the beginning of Liberia's "fourth wave" of EVD, acquired EBOV from....somewhere...somehow.[9] 

15M became ill from 13-Nov and was confirmed as EBOV infected 19-Nov.[7,8,9] He died 24-NOV.[12]

UPDATE #1: tally now stands at 3 cases - the 2 new cases among family members of 15M include his 8-year old brother and his father.[8,9] It has been said that 15M had no known contact with a survivor or relevant travel history.[9] 15M was previously described as 10M, but age amended in [9]) 
UPDATE #2: 153 contacts being monitored.[10]
UPDATE #3: WHO lists boy as 10-year old in 23NOV update. Aiyahh!  
UPDATE #4: Announcement of 10M death.[12]
UPDATE #5: Guess what? WHO says 15M.[13] Father, 40M.[13] 149 contacts including 10 healthcare workers.
UPDATE #6: 40M and 8M were discharged from hospital but some contacts still have a week of observation to complete.[14]

Information on how the initial infection for this cluster was acquired.

Time will may tell us more.

Reference...

1. http://www.focus-fen.net/news/2015/11/20/390066/one-new-confirmed-case-in-previously-ebola-free-liberia-who.html
2. http://www.reuters.com/article/2015/11/20/health-ebola-liberia-idUSL8N13F1HC20151120#LtSB8YECI4XoKEl3.97
3. http://www.theguardian.com/world/2015/nov/20/ebola-case-in-liberia-confirmed-by-who
4. http://www.itv.com/news/update/2015-11-20/ebola-case-confirmed-in-liberia/
5. http://www.nytimes.com/aponline/2015/11/20/world/africa/ap-af-ebola-west-africa.html?_r=0
6. http://africanspotlight.com/2015/11/20/new-ebola-case-discovered-in-liberia-un/
7. http://www.npr.org/sections/goatsandsoda/2015/11/20/456787852/ebola-returns-to-liberia-but-its-not-clear-how-the-10-year-old-got-it
8. http://www.bbc.com/news/world-africa-34882191
9. http://www.nytimes.com/2015/11/21/world/africa/ebola-case-in-10-year-old-confirmed-in-liberia.html?_r=0
10. http://www.reuters.com/article/2015/11/22/health-ebola-liberia-idUSL8N13H0CM20151122#Ug24kslkc6Qo48g0.97 
11. http://who.int/csr/disease/ebola/flare-up-liberia/en/
12. http://www.reuters.com/article/2015/11/24/health-ebola-liberia-idUSL8N13J1V820151124#bCYKBOZy3DTtz7US.97
13. http://apps.who.int/ebola/current-situation/ebola-situation-report-25-november-2015
14. http://www.trust.org/item/20151203193032-4wnba