Merck Animal Health Announces Registration of AQUAVAC® Strep Sa and NORVAX® Strep Si Vaccines in Vietnam

Vaccines Protect Against Serious Diseases Affecting Warmwater Fish 

MADISON, NEW JERSEY, March 10, 2014 – Merck Animal Health (known as MSD Animal Health outside the USA and Canada) today announced the registration of the AQUAVAC® Strep Sa and NORVAX® Strep Si vaccines in Vietnam. The vaccines protect against the two most significant strains of streptococcus, a highly prevalent disease affecting warm water fish.  

“We are pleased that we have obtained the registration for AQUAVAC Strep Sa and NORVAX Strep Si in Vietnam. Once available, these products will help producers protect their fish against streptococcus,” said Norman Lim, Merck Animal Health. “These important vaccines reflect Merck Animal Health’s commitment to supporting producers with effective vaccination and control programs, such as the ‘Strep Control: Your Tilapia Health’ program for tilapia producers.” 

Streptococcus affects warm water fish in both marine and freshwater environments and can result in mortality rates in fish as high as 70 percent. Merck Animal Health conducted extensive sampling of farms in the world’s most important tilapia-producing regions and found that streptococcus accounted for 70 percent of all pathogens collected, making it the most prevalent disease affecting tilapia. The two significant species are Streptococcus agalactiae and Streptococcus iniae. 


AQUAVAC Strep Sa provides protection against the biotype 2 strain of S. agalactiae, a strain found in Vietnam. In a large-scale field trial in an environment challenged by S. agalactiae biotype 2, AQUAVAC Strep Sa vaccinated tilapia saw a significant improvement in mortality, increased biomass of 15.6 percent, and feed conversion efficiency was improved by 10 percent when compared with unvaccinated control fish. In a laboratory test, AQUAVAC Strep Sa protected 85 percent of fish for over 30 weeks.

AQUAVAC Strep Sa provides specific protection against the biotype 2 strain of S. agalactiae, the main cause of streptococcosis in tilapia in Vietnam. Fish vaccinated with AQUAVAC Strep Sa are safe for human consumption. The Merck Animal Health ‘Strep Control Your Tilapia Health’ program, put in place to support farmers with their health management, will help producers confirm the strain and biotype present on their farm, help them develop a specific vaccination and health program and give them access to a variety of tools, equipment and expert advice to put in place a best practice approach and demonstrate performance of the health program. Producers can consult their Merck Animal Health representative or a fish health professional to learn about Merck Animal Health’s ‘Strep Control Your Tilapia Health’ program and AQUAVAC Strep Sa

NORVAX®Strep Si 

NORVAX Strep Si induces protective immunity in warm water fish against streptococcus caused by S. iniae . NORVAX Strep Si can be administered through a bath immersion for fish 3 grams and above and through injection for fish larger than 20 grams. The vaccine is registered for use in barramundi.

The vaccine has been proven to offer protection for at least 12 weeks in laboratory studies and 34 weeks in field trials. In a field trial, Asian sea bass injected with NORVAX Strep Si had survival rates of 100 percent after being challenged with S. iniae, while a control group had survival rates of 37.5 percent. In Asian sea bass receiving an immersion vaccination with NORVAX Strep Si, survival rates were 75 percent following challenge with S. iniae, compared to a survival rate of 22.5 percent in the control group.1 

For more information about AQUAVAC Strep Sa and NORVAX Strep Si, producers can consult their Merck Animal Health representative or a fish health professional.

About Merck Animal Health 

Today’s Merck is a global healthcare leader working to help the world be well. Merck Animal Health, known as MSD Animal Health in the United States and Canada, is the global animal health business unit of Merck. Merck Animal Health offers veterinarians, farmers, pet owners and governments one of the widest range of veterinary pharmaceuticals, vaccines and health management solutions and services. Merck Animal Health is dedicated to preserving and improving the health, well-being and performance of animals. It invests extensively in dynamic and comprehensive R&D resources and a modern, global supply chain. Merck Animal Health is present in more than 50 countries, while its products are available in some 150 markets. For more information, visit .

Merck forward-Looking Statement 

This news release includes “forward-looking statements” within the meaning of the safe harbor provisions of the United States Private Securities Litigation Reform Act of 1995. These statements are based upon the current beliefs and expectations of Merck’s management and are subject to significant risks and uncertainties. If underlying assumptions prove inaccurate or risks or uncertainties materialize, actual results may differ materially from those set forth in the forward-looking statements. 

Risks and uncertainties include but are not limited to, general industry conditions and competition; general economic factors, including interest rate and currency exchange rate fluctuations; the impact of pharmaceutical industry regulation and health care legislation in the United States and internationally; global trends toward health care cost containment; technological advances, new products and patents attained by competitors; challenges inherent in new product development, including obtaining regulatory approval; Merck’s ability to accurately predict future market conditions; manufacturing difficulties or delays; financial instability of international economies and sovereign risk; dependence on the effectiveness of Merck patents and other protections for innovative products; and the exposure to litigation, including patent litigation, and/or regulatory actions. 

Merck undertakes no obligation to publicly update any forward-looking statement, whether as a result of new information, future events or otherwise. Additional factors that could cause results to differ materially from those described in the forward-looking statements can be found in Merck’s 2014 Annual Report on Form 10-K and the company’s other filings with the Securities and Exchange Commission (SEC) available at the SEC’s Internet site (

1 Data on File.