Tag: incubation period

How Many Active Cases Are There in Rockland County?

Three new cases were just reported in the Rockland County measles outbreak, pushing the total count to 161 cases in an outbreak that has been going on since September of 2018.

These are record breaking numbers.

Misleading? Fear mongering? Isn't that ironic???
Misleading? Fear mongering? Isn’t that ironic???

So of course, it’s time to move the goalposts!

How Many Active Cases Are There in Rockland County?

The number of active cases in an outbreak is an important number.

It’s a sign that the outbreak is under poor control.

For example, there were 45 new cases of measles in Brooklyn this week, following reports of 33 new cases the previous week. In fact, in the past 21 days, the case count in Brooklyn went from 158 to 259, which likely means that there have been over 100 active measles cases in Brooklyn during that time.

What about Rockland County?

In the past three weeks, the case count in Rockland County has increased by 16.

Why is three weeks an important number?

Because that’s how long it takes to develop symptoms after they have been exposed to someone with measles.

The problem in Rockland County, as Ed Day said in his press conference, is that people hadn’t been cooperating with the health department. So it is hard to actually know how many active cases there are. Is it five cases, as someone at the health department recently told an anti-vaccine women impersonating a caller who was concerned about her infant?

If so, that’s five cases too many!

The most important thing to understand, is that as we continue to see new cases, there is no sign that the outbreaks are stopping.

And the only numbers that really matter are ZERO new cases for 42 days.

That’s when the outbreaks will be declared over.

Let’s hope that we get there before we are talking about a new number, someone dying with measles.

More on Active Cases in Rockland County


What Is a Vaccine?

You know what a vaccine is, right?

The word vaccine comes from the vaccinia virus that was in the original smallpox vaccine.
The word vaccine comes from the vaccinia virus that was in the original smallpox vaccine.

The flu shot you get each year is a vaccine.

Vaccine: A product that stimulates a person’s immune system to produce immunity to a specific disease, protecting the person from that disease. Vaccines are usually administered through needle injections, but can also be administered by mouth or sprayed into the nose.

Immunization: The Basics

The smallpox shot that Edward Jenner developed was a vaccine.

Vaccine Definitions

While that is an easy enough definition to understand, that there are many different types of vaccines does make it a little more complicated.

There are:

  • Live-attenuated vaccines – made from a weakened or attenuated form of a virus or bacteria
  • Inactivated vaccines – made from a killed form of virus or bacteria
  • Subunit, recombinant, polysaccharide, and conjugate vaccines – made from only specific pieces of a virus or bacteria
  • Toxoid vaccines – made to target a toxin that a bacteria makes and not the bacteria itself

And of course all of these types of vaccines work to produce immunity to specific diseases – vaccination.

Immunization: A process by which a person becomes protected against a disease through vaccination. This term is often used interchangeably with vaccination or inoculation.

Immunization: The Basics

What other definitions are important to know when you talk about vaccines?

  • active immunity – immunity that you get from having a disease (natural immunity) or getting a vaccine and making antibodies
  • adjuvant – a substance that helps boost your body’s immune response to a vaccine so that you can use a minimum amount of antigen, reducing side effects
  • antibodies – protective proteins that you make against antigens
  • antigens – specific substances (can be part of a virus or bacteria) that trigger an immune response
  • attenuation – a virus or bacteria that is made less potent, so that it can produce an immune response without causing disease
  • elimination – getting rid of a disease in a specific area
  • endemic – the baseline level of disease in an area
  • eradication – getting rid of a disease everywhere (smallpox)
  • epidemic – an increase in the number of cases of a disease over a large geographic area
  • herd immunity – when enough people in a community are protected and have immunity, so that disease is unlikely to spread
  • immunity – protection against a disease
  • incubation period – how long it takes to develop symptoms after you are exposed to a disease
  • outbreak – an increase in the number of cases of a disease over a small geographic area
  • pandemic – an increase in the number of cases of a disease over several countries or continents
  • passive immunity – temporary immunity that you get after being given antibodies, either via a shot of immunoglobulin or a mother’s antibodies are transferred to her baby through her placenta
  • placebo – classically defined as “a comparator in a vaccine trial that does not include the antigen under study”
  • quarantine – isolating someone so that they don’t get others sick
  • titer – an antibody count that can often be used to predict immunity

Got all of that?

So what about variolation, the process that was used before Jenner developed his smallpox vaccine? Was that also a vaccine?

It did produce immunity to smallpox, which is the basic definition of a vaccine, but still, variolation is typically concerned an immunization technique and not a vaccine.

More on Vaccine Definitions

How Contagious Is Measles?

Did you hear about the folks in New York who got quarantined isolated on the Emirates plane from Dubai?

Turns out that about 10 passengers had the flu or other cold viruses.
Although the worry was likely about MERS, it turns out that about 19 passengers had the flu or other cold viruses.

News like that and folks getting exposed to other infectious diseases, probably has them wondering just how contagious these diseases are. Do you have to be sitting next to someone to get them? In the same row? On the same floor?

Understanding Your Risk of Catching a Disease

Fortunately, most diseases are not terribly contagious.

We worry about some things, like SARS and Ebola, because they are so deadly, not because they are so contagious or infectious.

Wait, contagious or infectious? Aren’t they the same thing?

To confuse matters, some infectious diseases aren’t contagious, like Lyme disease. And some vaccine-preventable diseases are neither infectious nor communicable. Think tetanus. You may have never thought of it that way, but you aren’t going to catch tetanus from another person. Of course, that’s not a good reason to skip getting a tetanus shot!

To understand your risk of getting sick, you want to understand a few terms, including:

  • infectious disease – a disease that can be transferred to a new host
  • communicable – an infectious disease that can be transferred from one host to another
  • non-communicable – a non-infectious disease which can not be transferred from one host to another
  • contagiousness – an infectious disease that is easily transferred from one person to another
  • infectivity – the ability of an infectious agent to cause an infection, measured as the proportion of persons exposed to an infectious agent who become infected. Although this doesn’t sound much different from contagiousness, it is. The Francisella tularensis bacteria is highly infectious, for example, to the point that folks exposed to a culture plate are given antibiotics or put on a fever watch. Few of us get tularemia though, because transmission is through tick bites, hunting or skinning infected rabbits, muskrats, prairie dogs and other rodents, or inhaling dust or aerosols contaminated with F. tularensis bacteria. So if you get exposed, you will probably get sick, but there is a low probability for getting exposed.
  • incubation period – the time it takes to start having symptoms after you are exposed to an infectious disease. A longer incubation period increases the chances that someone will get exposed to a disease and travel home before getting sick. A shorter incubation period, like for influenza, means that a lot of people can get sick in a short amount of time.
  • contagious period- the time during which you can spread the illness to other people and may start before you have any symptoms
  • quarantine – used to separate people who have been exposed to a contagious disease and may become sick, but aren’t sick yet
  • isolation – used to separate people who are already sick with a contagious disease
  • transmission – how the disease spreads, including direct (direct contact or droplet spread) vs indirect transmission (airborne, vehicleborne, or vectorborne)
  • R0 (r nought) – the basic reproductive number or the number of new infections originating from a single infectious person among a total susceptible population
  • Rn – the net reproductive number, which takes into account the number of susceptibles in a community
  • infectious period – how long you are contagious

Got all that?

How Contagious Is Measles?

If not, understanding how easily you can get measles should help you understand all of these terms.

Measles is highly contagious, which is likely why all of the Brady kids got sick.
Measles is highly contagious, which is likely why all of the Brady kids got sick.

Measles is highly contagious, with a very high R0 number of 12 to 18.

That’s because:

  • the measles virus can live for up to two hours on surfaces and in the airspace where an infected person coughed or sneezed
  • infected people are contagious for up to four days before they have a rash and even know that they have measles, so expose lots of people even if they get put in isolation once they get diagnosed
  • infected people continue to be contagious for up to four days after the rash appears, so can continue to expose people if they aren’t put in isolation

So you don’t need to have someone with measles coughing in your face to get sick. If they coughed or sneezed at the grocery store, on the bus, or at your doctor’s office and then you entered the same area within two hours, then you could be exposed to the measles virus and could get sick.

Why don’t we see at least 12 to 18 people in each measles outbreak anymore?

That’s easy. The definition for R0 is for a total susceptible population. Most folks are vaccinated and protected, so even if they are around someone with measles, they typically won’t get sick.

Still, up to 90% of folks who aren’t immune and are exposed to measles will catch it. That includes infants too young to be vaccinated, kids too young to be fully vaccinated, and anyone who has a true medical exemption to getting vaccinated.

The measles has a very high R0 is easier to see when you compare it to those of some other diseases

 

Infection R0
Diphtheria 6-7
Ebola 1.5-2.5
Flu 1.4-4
MERS 2-8
Mumps 4.7
Pertussis 5-17
Polio 2-20
RSV 3
SARS 2-5
Smallpox 5-7
Varicella 8-10

Why such a big range for some diseases?

These are estimates and you are more or less contagious at different stages of each illness.

Fortunately, in most cases you can just get vaccinated and protected and don’t have to worry too much about them.

More on the Contagious Periods of Diseases

The Latest Measles Outbreak in Kansas

Several things are troubling about the measles outbreak in Kansas.

For one thing, it involved a lot of infants who were too young to be vaccinated. Their parents didn’t get to make a choice about getting vaccinated or getting measles. They got measles.

There are at least 18 cases of measles in current Kansas outbreak.
An ongoing measles outbreak in Kansas is up to 18 cases.

Also, as the case count climbed to 22 before ending, we are only now learning how the outbreak got started.

Greg Lakin, the chief medical officer for the Kansas Department of Health and Environment, said the current outbreak started when an infant who was too young to be vaccinated picked up the virus in Asia. That infant then returned to a Johnson County day care.

What You Need to Know About the JoCo Outbreak

But what does too young to be vaccinated mean?

Remember that if you are traveling out of the country, infants should get their first MMR early, as early as six months of age.

Update on the Measles Outbreak in Kansas

Since the outbreak in a daycare in Johnson County was discovered on March 8, a total of 22 measles cases have been identified, including:

  • 14 Johnson County residents
  • three Linn County residents
  • one Miami County resident not associated with the daycare

The latest cases could have exposed other people to measles at:

  • Cornerstone Presbyterian Church in the Lobby and Sanctuary; 13300 Kenneth Rd., Leawood, KS; April 8 from 10:30 a.m.to 1:30 p.m.
  • Blue Mound Federated Church; General Delivery, Blue Mound, KS; April 1 from 10:00 a.m. to 1:00 p.m.
  • Olathe Health Family Medicine; 302 N.1st St, Mound City, KS; March 26 and 28 from 8:00 AM to 5:30 PM
  • Olathe Health Family Medicine; 1017 E. Market St, La Cygne, KS; March 27 from 8:00 AM to 5:30 PM, March 29 from 8:00 a.m. to 5:30 p.m, March 30 from 8:00 a.m. to 2:30 p.m., and April 2 from 8:00 a.m. to 3:30 p.m.
  • Casey’s General Store; 207 S. 9th St, Mound City, KS; March 26 from 11:30 AM to 2:00 PM, March 28 from 12:00 PM to 2:30 PM, March 30 from 1:00 p.m. to 3:00 p.m., and April 2 from 7:30 a.m. to 9:30 a.m
  • Casey’s General Store; 406 E. Market St, LaCygne, KS;March 27 from 12:00
    PM to 2:30 PM
  • Linn County Judicial Building; 318 Chestnut St., Mound City, KS; March 30 from 1:30 p.m. to 5:00 p.m.
  • Applebee’s; 16110 W. 135thSt., Olathe, KS; March 30 from 5:30 p.m. to 8:30 p.m.
  • Main Street Liquor; 411 E. Main St., Osawatomie, KS; March 30 from 9:30 p.m. to 11:00 p.m.
  • Dollar General; 110 S. 9thSt., Mound City, KS;March 29 from 5:45 p.m. to 8:00 p.m.
  • Auburn Pharmacy; 625 E Main. St, Mound City, KS; on March 13th from 4:15 PM to 6:45 PM
  • Aldi’s; 15290 W. 119th St Olathe, KS 66062; on March 2nd from 3:00 PM to 5:00 PM
  • Payless Discount Foods; 2101 E. Santa Fe St, Olathe, KS; on March 6th from 10:00 AM to 12:30 PM
  • El Potro Mexican Café; 602 N Pearl St, Paola, KS on March 7th from 4:00 PM to 8:00 PM
  • Children’s Mercy Hospital Kansas Emergency Department; 5808 W 110th St, Overland Park, KS on March 8th and March 10th in the morning
  • AMC Dine – In Studio 28; 12075 S. Strang Line Rd, Olathe, KS; March 9th from 3:30 PM to 7:30 PM
  • Budget Coin Laundry; 798 E Main St, Gardner, KS; on March 9th from 8:00 PM – 11:00 PM
  • Olathe YMCA swimming pool and locker room; 21400 W. 153rd St, Olathe, KS; on March 10th from 9:30 AM to 1:00 PM
  • Bath and Body Works at Legends Outlets; 1803 Village W Pkwy, Kansas City, KS; on March 10th from 1:00 PM to 3:00 PM
  • Crazy 8 at Legends Outlets; 1843 Village W Pkwy, Kansas City, KS ; on March 10th after 1:00 PM to 3:00 PM
  • Orange Leaf; 11524 W 135th St Overland Park, KS; on March 10th from 3:00 PM to 6:00 PM
  • Chick-fil-A; 12087 S Blackbob Rd, Olathe, KS on March 24th 8:15 PM till Close
  • Olathe YMCA – ENTIRE FACILITY INCLUDING CHILDCARE AREA; 21400 W. 153rd St, Olathe, KS on March 22nd and 23rd from 8:00 AM to 3:00 PM
  • Walgreens; 7500 Wornall Rd, Kansas City, MO on March 22nd, 6:00 PM to 8:00 PM
  • Chuck E. Cheese’s; 15225 W 134th Pl, Olathe, KS on March 21st, 1:00 PM to 4:00 PM

If you were exposed and aren’t immune to measles (two doses of the MMR vaccine provide good protection), then you should watch for signs and symptoms to develop 10 to 21 days after your last exposure (in quarantine).

With the new exposures, that means that we could expect to see new cases associated with this outbreak any time between now and April 29th (the last exposure and the longest incubation period).

A History of Measles Outbreaks in Kansas

Some folks probably recall that this isn’t the first big measles outbreak in Kansas.

One of the largest measles outbreaks of 2014 was in the Kansas City metropolitan area. That year, at least 28 people developed measles, including a newborn who was only two weeks old.

In addition to the outbreak in Kansas City, there was another large outbreak that year in Sedgwick County – Wichita, Kansas.

And like most measles outbreaks, other states were affected too. Someone from Texas developed measles after getting exposed to measles at a softball tournament in Wichita.

More recently, outbreaks in Kansas have included:

  • a suspected case at William Allen White Elementary School in Lyon County, Kansas which has led to the quarantine of unvaccinated students for 3 weeks (2017)
  • a case in Butler County, Kansas. (2017)
  • a case in Sedgwick County, Kansas, a child too young to be vaccinated who may have been exposed at a church. Three other exposed infants who were too young to be vaccinated and who were considered at risk to get measles in this outbreak received immunoglobulin treatment. (2017)
  • a second case in the Wichita, Kansas area, this time in Sedgwick County, with exposures at a church, dental office, elementary school, and multiple stores over at least 3 days. (2017)

Why are there still so many measles outbreaks in Kansas?

Like in other places with outbreaks, it is likely explained by relatively high levels of non-medical exemptions and clusters of unvaccinated children and adults.

Hopefully this outbreak will be a good reminder that vaccines are necessary and everyone will get their kids caught up and protected.

What to Know About the Measles Outbreak in Kansas

Kansas is in the middle of another large measles outbreak and as usual, it is mostly among those who are unvaccinated, including many too young to be vaccinated.

More on the Measles Outbreak in Kansas

Updated on April 21, 2018