Officials from the United Nations and the World Health Organization expressed concern on Thursday over data showing the first weekly rise in new Ebola cases this year, countering the downward trend in the disease that has ravaged three West African nations.

The 124 new cases — 39 in Guinea, five in Liberia and 80 in Sierra Leone for the week ended Feb. 1 — amounted to a relatively small increase from the 99 new cases the week before, and paled in comparison with the hundreds of new cases per week that traumatized those countries and alarmed the world in the later months of 2014.

Since then, a global outpouring of money and resources has helped to severely limit what has been the worst Ebola outbreak in history, with more than 22,000 cases and nearly 9,000 deaths. Attention has refocused in the three countries on trying to restore a semblance of normalcy.