A Case of Statin-Induced Myopathy
Explore Your Options: Modified-live And Killed Vaccines
A sound vaccination protocol lays the groundwork for a healthy herd. Taking time to understand the different vaccine options is an important part of making informed decisions that ensure your cattle are in the best position possible to navigate disease challenges.
"Both modified-live virus and killed virus vaccines have been shown to protect cattle against common respiratory and reproductive diseases; however, there are some key differences in how each of them stimulates immunity," said Dr. Craig Jones, DVM, director of cattle professional services veterinarians, Boehringer Ingelheim. "It is important for producers to understand the advantages and limitations associated with each."
Modified-live virus vaccinesMLV vaccines contain a weakened, or attenuated, form of a live virus. Because the virus has been altered, it should not cause clinical disease, but will very closely mimic a true infection.
Once the vaccine is administered, the virus will replicate within the animal's system and create the opportunity for an immune response. Compared to KV vaccines, MLV vaccines generally provide a more rapid, longer-lasting and broader immunity with one dose, since the virus is able to replicate and behave closer to the way it would during a natural infection.¹
Although MLV vaccines may stimulate a broader, more complete immune response, there are some other factors to consider. "Modified-live virus vaccines have a greater risk of causing an abortion in pregnant cows, if not used appropriately and according to label," explained Jones. "In addition, MLVs must be reconstituted [mixed], and may require more attention to detail when it comes to proper use, handling and storage. These factors do not preclude my use or recommendation of MLVs; they are simply things we must keep in mind prior to and when using."
Once MLVs are mixed, they should be kept cold and out of sunlight. Following Beef Quality Assurance guidelines, mix only as much vaccine as can be used in one hour or less. MLV products should not be stored for later use.
Killed virus vaccinesKV vaccines are safe at all stages of pregnancy. They typically do not require reconstitution, and they have a longer shelf life relative to MLV vaccines.
The immune response following use of a KV vaccine will be slower to develop. "Killed vaccines contain an inactivated, or killed, antigen that is incapable of replicating in the animal's system," Jones pointed out. Because the killed virus does not replicate, it usually requires a booster dose in two to four weeks to stimulate a complete immune response.
"As compared to MLV vaccines, a dose of killed virus vaccine may contain more viral antigen, or pieces of the virus, in order for the immune system to recognize and respond to the antigen," confirmed Jones. "Because there is more antigen needed, killed vaccines often cost more."
Things to consider"When it comes to building a protocol, you don't necessarily have to choose between the two types of vaccines," advised Jones. "In fact, there are many veterinarians and producers who choose to incorporate both options into their protocols."
Below are some things to consider when choosing the products to best protect against the disease challenges facing your cattle:
1. Work with a veterinarian.
"The whole point of vaccination is to help animals remain healthy, while minimizing the risk of economically important diseases that are prevalent in the area where the cattle are being, or will be, managed," Jones stressed.
Your local veterinarian can help guide this discussion and provide insight as to which diseases are economically significant and prevalent. Whether you're talking about parasite management or protecting against reproductive and respiratory losses, working with a veterinarian is the first step.
2. Have a written herd health calendar.
Once you have determined which diseases you should vaccinate against, consider using a herd health calendar to help with timing. This will ensure that vaccines are given prior to any potential health risks and your cattle are protected.
"I always recommend having a written health protocol and records of vaccine and other product administration," said Dr. Jones. "When health activities are recorded and visible for others in the operation to see, we have greater protocol compliance and more awareness of herd health events."
3. Stay on label.
Different types of vaccines behave differently and will perform differently. Paying attention to the label is extremely important, and will ensure the vaccine is aligned with your expectations. Product labels will also inform you about the correct route of administration and the dose needed.
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Commentary: Four Years In, Why Are Some People Hesitant About COVID-19 Vaccine Boosters?
SINGAPORE: I felt something akin to nostalgia when I visited the Joint Testing and Vaccination Centre at Kaki Bukit last week to get a COVID-19 booster jab.
This was the location where, almost exactly a year ago, I received my last booster. And while the COVID-19 landscape in Singapore has changed in the ensuing 12 months, nearly everything at the centre was reassuringly familiar.
There were the very friendly members of staff helping to guide people quickly and efficiently through the process, from registration to injection to observation.
Just like the last time, a small, circular sticker was issued to indicate which vaccine each person had elected to get - green for Pfizer, yellow for Moderna (having been a Moderna man before, I decided to mix it up a little by asking for the Pfizer jab). And there was the handing over of the leaflet telling me to limit physical activity for the next couple of weeks.
In fact, the only thing that differed from my last visit was that there weren't many people getting their jabs. In the observation room, I was one of three people.
A year ago, the place was busy enough for there to be slight pauses at each stage of the process as the staff worked their way through the steady stream of people wanting to get protected.
This time round, I walked through the process very quickly, being dealt with immediately at every stage. Admittedly, this was on an early Friday evening, which is perhaps a time when many people were out and about doing other things.
Nonetheless, I expected the centre to be busier. With Singapore experiencing a spike in COVID-19 infections and with declining resistance cited as one of the reasons for this, I thought that many people would have used that as a prompt to get up to date with their vaccinations.
The estimated number of COVID-19 infection cases for the week of Dec 10 to Dec 16 was the highest recorded for the year, with 58,300 cases for epi-week 50, up from the previous record of 56,043 cases in the preceding week.
A total of 965 new COVID-19 patients were admitted to hospitals in the same week, up from 763 the previous week.
Does India Have Enough Vaccine Reserves To Combat Another Covid Wave?
Vaccine makers in India have a limited stockpile of doses, even as COVID-19 threatens to rear its head this winter season, reports Sohini Das.
IMAGE: A beneficiary is being inoculated with a booster dose of the COVID-19 vaccine, amid a surge in the coronavirus cases across the world, at a centre, in Ranchi, December 26, 2022. Photograph: ANI Photo
Pune-based Gennova Biopharmaceuticals has one million doses of its Gemcovac-OM (an Omicron-specific mRNA booster vaccine).
The health ministry's CoWIN portal shows stocks of Serum Institute of India's Covovax (its vaccine produced in partnership with Novavax) at some vaccination centres.
However, sources revealed that SII does not have any stockpile at a company level.
According to CoWIN data, only 73 vaccination centres are currently active in India, of which 32 are government-run.
Most of the centres are offering Covovax vaccine.
On Tuesday, 58 vaccinations were administered in India, of which only one was a precautionary dose taken by a senior citizen (aged above 60 years).
Twenty-eight vaccinations were administered to people in the 18-59 years age group.
An official of Gennova confirmed that the company has about one million doses of Gemcovac-OM, the first and only COVID-19 booster vaccine made available in India against the highly transmissible Omicron variant to have received the emergency use authorisation or EUA from the office of the Drugs Controller General of India.
The JN.1 sub-variant is a descendant of BA.2.86 (also known as Pirola), which itself is a sub-variant of the widely circulating Omicron.
"The booster vaccine helps in generating antibodies and memory immune responses specific to the Omicron variant, which can reduce the probability of infection and hospitalisation, and even prevent future waves of the pandemic," the company said.
Unlike other mRNA vaccines, Gemcovac-OM, launched in June this year, remains stable at 2-8 degrees Celsius.
"The vaccine is available at 50 centres across major cities in India and can be obtained via the Co-WIN portal and vaccinator app. Gennova has also tied up with an agency that can vaccinate people at home," the company said.
Meanwhile, SII is gearing up to apply for licensing a vaccine for the JN.1 variant, the company said.
It now has an XBB1 variant vaccine that is very similar to the JN.1 variant.
In the coming months, SII plans to obtain a licence for this vaccine in India.
Bharat Biotech does not have any stockpile of Covaxin, its whole-virion (an entire virus particle) inactivated COVID-19 vaccine.
Its production had stopped around April last year, and the stockpile was subsequently exhausted.
Stocks for the intranasal vaccine iNCOVACC have also run out.
An immediate response could not be elicited from Biological E on vaccine stock.
The Hyderabad-based company made Corbevax, which had got approval to be used as a mix-and-match booster after two doses of Covaxin or Covishield.
A vaccine industry source elaborated that the manufacturers were not gearing up to produce more doses because of two reasons.
One is low or almost no demand for vaccines from either the private or the public sector.
Secondly, all of these vaccines have an EUA status that does not allow the manufacturers to distribute them through pharmacies.
"One cannot release the vaccine onto the private market (through the pharmacy or other distribution channels) as they have an EUA status. Vaccines have to be ordered either by the government or private centres registered with Co-WIN. So, unless orders are placed no one can produce doses and create a stockpile," said the source on grounds of anonymity.
India SARS-CoV-2 Genomics Consortium chief NK Arora has said that no additional dose of vaccine is required against JN.1 at the moment.
According to him, precaution is required for those aged above 60 years, having co-morbidities or on drugs that suppress immunity (like cancer patients).
"In case these people have not yet taken their third dose, they are advised to take precaution," he said recently.
Going by the current scenario, demand is unlikely to rise anytime soon.
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