Pandemic & Infectious Disease — 2026-04-03

Active Outbreak Tracker

Mpox (Monkeypox) — Democratic Republic of Congo & Global

• Status: Ongoing; clade I outbreaks continuing in DRC; clade II circulating in multiple countries worldwide
• Key Development: NanoViricides, Inc. announced on April 1, 2026 that a Phase II clinical trial of its mpox treatment NV-387 is expected to begin soon in the Democratic Republic of Congo, with clinical trial site preparations underway. This represents the first targeted antiviral treatment candidate to enter Phase II testing specifically for the DRC outbreak context.
• Response: Trial site preparations are advancing; NanoViricides is coordinating with in-country partners to initiate the study. The CDC continues to monitor both clade I and clade II mpox outbreaks globally.

1 sources

pharmiweb.com

pharmiweb.com

Respiratory Illnesses (COVID-19, Influenza, RSV) — United States

• Status: Low-to-minimal activity nationally; 2025–2026 season winding down
• Key Development: The CDC has indicated it does not anticipate producing additional outlook updates during the remainder of the 2025–2026 respiratory season, signaling a period of low transmission across COVID-19, influenza, and RSV. Real-time Rt estimates for U.S. states continue to be tracked by CDC's Center for Forecasting and Outbreak Analytics.
• Response: California's Department of Public Health has extended RSV immunization with monoclonal antibodies (nirsevimab and clesrovimab) for eligible infants and children through April 30, 2026. Insurance coverage of RSV immunization will continue through the period.

4 sources

cdc.gov

Global Measles Outbreaks | Global Measles Vaccination | CDC

cdc.gov

cdc.gov

cdc.gov

Respiratory Illnesses Data Channel | Respiratory Illnesses | CDC

cdc.gov

cdc.gov

Pandemic Preparedness — Global Policy Watch

• Status: Elevated concern; UN High-Level Meeting on PPPR approaching in 2026
• Key Development: The Lancet published a new article this week urging world leaders to elevate spillover prevention — stopping pathogens from jumping from animals to humans — at the upcoming 2026 UN High-Level Meeting on pandemic prevention, preparedness, and response. Authors warn that global attention to pandemic readiness has waned amid competing crises including inflation and armed conflict.
• Response: The piece calls for concrete political commitments and investment in zoonotic disease surveillance as foundational pandemic prevention infrastructure ahead of the UN meeting.

Vaccine & Treatment Pipeline

• NV-387 (Mpox Antiviral) (NanoViricides, Inc.): Phase II clinical trial expected to commence imminently in the Democratic Republic of Congo. Trial site preparations are underway. NV-387 is a broad-spectrum antiviral candidate targeting mpox, with the DRC selected as the site given the ongoing clade I outbreak burden.

• COVID-19 Vaccine (Antigen Composition Update) (WHO TAG-CO-VAC): The WHO Technical Advisory Group on COVID-19 Vaccine Composition continues to closely monitor the genetic and antigenic evolution of circulating SARS-CoV-2 variants in preparation for May 2026 antigen composition deliberations. The group is soliciting data on immune responses to infection and vaccination, and on vaccine performance against current variants.

• VLA15 / Lyme Disease Vaccine (Pfizer/Valneva): Following the announcement of over 70% efficacy in the Phase 3 VALOR trial, Pfizer has confirmed it will seek FDA approval for the six-strain Lyme disease vaccine candidate. Michigan alone has seen Lyme disease cases skyrocket 168% over five years, and no safety concerns were observed in trial participants as young as age five.

Expert Analysis

A new commission published in The Lancet this week argues that spillover prevention — stopping pathogens from crossing the animal-human interface — must be elevated at the 2026 UN High-Level Meeting on pandemic prevention, preparedness, and response (PPPR). The authors note that "the devastation caused by COVID-19 brought pandemic prevention, preparedness, and response to the forefront of the global political agenda," but warn that momentum has stalled as governments contend with inflation, war, and other immediate crises. The piece calls for urgent, measurable political commitments to zoonotic surveillance and ecological risk reduction as the most cost-effective form of pandemic prevention.

The timing of the commission is significant: it arrives as the global health security community debates whether the lessons of COVID-19 have been sufficiently institutionalized. The concurrent launch of a Phase II monkeypox antiviral trial in the DRC underscores both the ongoing threat posed by zoonotic pathogens and the urgency of having countermeasures ready before the next large-scale spillover event. Experts across the field have consistently argued that the DRC's clade I mpox outbreak — which has proven harder to contain than clade II — represents precisely the kind of endemic, high-burden situation where novel antivirals could save lives and reduce transmission chains before international spread occurs.

Global Health Security

WHO COVID-19 Vaccine Composition Deliberations (May 2026): The WHO Technical Advisory Group on COVID-19 Vaccine Composition (TAG-CO-VAC) formally requested data submissions to inform upcoming antigen composition decisions. The call covers immune response data, variant surveillance, and real-world vaccine effectiveness data against currently circulating SARS-CoV-2 strains. This annual process determines the formulation of updated COVID-19 vaccines globally.

The Lancet Calls for Spillover Prevention at 2026 UN Summit: A high-profile commentary published this week in The Lancet urges governments to prioritize the prevention of animal-to-human pathogen spillover at the upcoming UN High-Level Meeting on PPPR. The authors argue that reducing ecological disruption, curtailing wildlife trade, and investing in One Health surveillance are the most upstream and cost-effective pandemic preparedness interventions available.

California Extends RSV Immunization Coverage Through April 2026: The California Department of Public Health confirmed that RSV immunization with monoclonal antibodies (nirsevimab and clesrovimab) for eligible infants and children will continue through April 30, 2026, with ongoing insurance coverage. This reflects state-level efforts to fill pediatric respiratory protection gaps as the federal public health landscape remains in flux.

What to Watch Next

• NV-387 Phase II Trial Enrollment (DRC): Now that site preparations are underway for NanoViricides' mpox antiviral trial in the DRC, the key milestone to watch is the formal start of patient enrollment. Interim safety and efficacy data from this trial could shape emergency-use authorization pathways for the first mpox-specific antiviral in the region hardest hit by clade I outbreaks.

• WHO May 2026 COVID-19 Vaccine Composition Decision: The WHO TAG-CO-VAC is actively soliciting data ahead of its May 2026 meeting to determine which SARS-CoV-2 antigens should be included in updated COVID-19 vaccines. This decision will directly affect vaccine formulations available globally for the 2026–2027 season, making the upcoming variant surveillance data submissions a critical watch item.

• UN High-Level Meeting on Pandemic Preparedness (2026): With The Lancet and other expert bodies now publishing preparatory analyses, the 2026 UN High-Level Meeting on pandemic prevention, preparedness, and response is shaping up to be a pivotal moment for global health governance. Whether member states will commit to enforceable spillover prevention frameworks — or settle for aspirational language — will have long-term consequences for pandemic risk.