The H1N1 Primer for Pregnant Women

Midwifery Today, 2009.
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Read also: Pregnancy and the H1N1 Flu Virus

This first wave of the H1N1 outbreak in North America has now passed, providing us with important information. The Centers for Disease Control and Prevention (CDC) predicts another wave to come around December and perhaps again in the New Year. Typically the Respiratory Synctial Virus (RSV) flu and seasonal flu arrive in January or February and last until April or May. Another H1N1 wave would overlap with the regular flu season. Women who are pregnant are particularly concerned about the choices they must make to protect themselves and their baby. This information has been compiled to help answer the most common questions.

I have heard that the H1N1 Flu carries more risk when I am pregnant. Is this true?

Any flu or illness carries additional risks in pregnancy, and the H1N1 virus is no different. Although the majority of H1N1 flu cases have been mild and similar to usual flu, pregnant women and their unborn babies have been found to be more vulnerable to this particular virus. Because of changes to the immune system during pregnancy, the virus is harder to shake. And during the second or third trimesters, the mother’s lung capacity is reduced, which can make a respiratory infection like the flu more serious. A small minority of people will experience severe symptoms. Pregnant women are among the highest risk groups for this syndrome, with women in their third trimester at greatest risk. That is why pregnant women are at the top of the government’s priority list for receiving the vaccine.

What about risks to my baby?

As long as the flu is mild, most babies weather the mom’s illness just fine. They don’t get sick because the virus does not pass through the placenta. Some research indicates that any fever in pregnancy can slightly increase the likelihood of birth defects, early labor and meconium-stained amniotic fluid. Studies also suggest that the incidence of autism and schizophrenia is seven-fold higher in the children of women who were sick with the flu during pregnancy. Ironically, there is also some animal research that suggests immune response to flu immunization can produce the same increase. Exposure in the womb to the 1918 flu resulted in a 17% greater likelihood of heart disease sixty years later.

How likely is it that a serious complication will occur if I get H1N1 while I’m pregnant?

Many pregnant women have had the flu without developing severe symptoms. However, we are just beginning to discover some important facts. Although pregnant women constitute about one percent of the population, they have constituted about nine percent of those ill with H1N1 who have required hospitalization for complications. This has important implications for pregnant women. While perfectly healthy people can develop complications, those who are most at risk of serious illness during pregnancy are the same as in the general population: women who already have other health factors significantly affecting the pregnancy, like pre-existing asthma. Other factors that can contribute to increased risk include neurological disorders, diabetes, kidney or lung disease, lupus and any other significant underlying illness. If you are experiencing a low-risk pregnancy, it is less likely that you will develop complications.

There is no way to accurately predict what percentage of people infected with H1N1 will become seriously ill and require hospitalization. The percentage appears to be small—less than one percent—and some sources estimate as low as one-tenth of a percent. We know a little more about what happens to the people who do get sick enough to need medical intervention. Many people require assisted ventilation and approximately 1 out of 3 patients may lose the ability to oxygenate through their lungs. These individuals will need to be placed on extracorporeal membrane oxygenation (ECMO), treatment with a machine that oxygenates the blood, until their lungs heal enough to resume the function of oxygenation. The typical length of time in the intensive care unit (ICU) is 7–12 days. These are serious life-saving interventions, which are seldom needed in routine flu outbreaks.

How many people die from H1N1?

Our best statistics come from the Australia/New Zealand Intensive Care (ANZIC) study, since they have already gone through their flu season this year. They calculated that over the three-month period there were 28.7 documented cases of H1N1 flu per million inhabitants which required admission into the ICU. Of the 722 patients, 66 (9.1%) were pregnant women. Four hundred fifty-six out of the 706 patients for which there were available records (64.6%) underwent mechanical ventilation for approximately eight days. At the end of the study, 103 of the 722 patients (14.3%) had died and 114 remained in the hospital.

As of November 6, 2009, 897 people have been hospitalized in Oregon for complications resulting from the H1N1 virus. Of those hospitalized, there were 26 deaths (2.9%). A study in California of the first 1088 patients hospitalized in 2009 with H1N1 showed an 11% death rate. Around 20% of patients requiring ECMO were included in those deaths.

Approximately one-third of all deaths result from contracting a secondary lung infection: usually bacterial I. pneumonia or Staphylococcus aureus. If you have previously received a one-time pneumococcal vaccine, then you would most likely have immunities from at least seven predominant strains, or possibly 23, depending upon the vaccine you received. There is no vaccine for Staphylococcus aureus.

How will I know I have H1N1 if I get sick?

The CDC has described the symptoms experienced by individuals with swine flu. About 90 percent reported fever, 84 percent reported cough and 61 percent reported a sore throat—all similar to what is seen with seasonal flu. But about one in four cases have also involved either vomiting or diarrhea, which is not typical for the normal flu bug. You will probably not know the difference unless you are tested by your physician. False negatives occur with 34% of the Rapid antigen tests used to identify H1N1, which could delay important treatment with an antiviral. All Influenza A cases are now being treated as if they were H1N1, since that is the predominant flu presenting at this time.

Severe symptoms that require hospitalization generally begin three to five days after the onset of normal flu symptoms, and the need to get to a hospital can develop very rapidly.

What should I do if I get sick?

You should call your midwife or physician as soon as possible and consider your options. Prompt antiviral treatment for pregnant women has been shown to reduce the risk of serious complications. Even if you aren’t yet sick but have been exposed to a known case of H1N1 flu, most governmental health organizations recommend taking an antiviral, stating that the risks from the virus are believed to be greater than the unknown risks to the fetus from antiviral drugs (called Tamiflu and Relenza). Some naturopathic physicians question this approach as faulty reasoning. They would recommend boosting your immune system with appropriate vitamins, botanicals and homeopathic treatments.

Are antiviral drugs really safe in pregnancy?

The chemical names of drugs used as antivirals are oseltamivir, zanamivir, amantadine and rimantadine. They are all “Pregnancy Category C” medications, meaning that we have no evidence that they are harmful, but no clear evidence that they are safe. Both amantadine and rimantadine have been demonstrated to cause birth defects in animal studies when given at very high doses. However, no adverse effects to pregnant women or their babies have been reported among women who received oseltamivir or zanamivir during pregnancy. What is of most importance is that Tamiflu (oseltamivir), the most recommended antiviral for H1N1, must be administered within 48 hours of the start of flu symptoms in order for it to have any benefits for reducing the severity of the flu. If you suspect that you are becoming ill with the flu and wish to utilize this option, it is important to contact your physician right away.

On December 2 Dr. Fiona Godlee, editor-in-chief of the British Medical Journal (BMJ), published online a review done by BMJ and Great Britain’s Channel 4 News on the use of Tamiflu (oseltamivir). The authors of the new review, which updates a review published in 2006, analyzed 20 published clinical trials of Tamiflu that examined prevention, treatment and adverse reactions. Based on the data available to them, the authors of the new review concluded that they have “no confidence in claims that Tamiflu reduces the risk of complications of influenza in otherwise healthy adults,” and said the drug should not be used in routine control of seasonal flu.

Whether or not you opt to treat with antiviral medication, it is important to take steps to strengthen your immune system with vitamins, probiotics, plenty of rest and healthy meals.

I like the idea of using natural treatments instead of drugs. How can I reduce my risk of illness and help my body fight the flu?

First, you can diminish risk of contracting or spreading H1N1 by following some practical steps. Wash your hands frequently and refrain from touching your eyes, nose or mouth. Hug, rather than kiss, family members and friends. Carry and use your own pen when making purchases with credit. Use antibacterial or tea tree oil wipes on phones, keyboards, computer mouse devices and store cart handles. Cough or sneeze into your arm instead of a hand. Avoid shaking hands or carry alcohol-based sanitizers to use afterwards. Wash your hands after changing a diaper.

Natural health care providers recommend vitamins, herbs and homeopathic aids that may help you recover more quickly from illness. While no one can claim such supplements will prevent or cure the H1N1 flu, we can provide suggestions that are generally thought to strengthen the overall immune system. Following are the recommendations of Drs. Ed and Elena Hofmann-Smith from the Natural Childbirth and Family Clinic in Portland, Oregon:

Vitamin D3 is necessary for a component of the innate anti-infection response that is found in all primates studied so far. (Vitamin D is created in our bodies by exposing the skin to sunlight.) There are those researchers that believe that the natural drop in vitamin D levels during the dark seasons is at least part of the reason we have cold and flu epidemics during the winter. [If this is the case, it] means we have to supplement if we want the full benefit of the vitamin D-dependent systems….What is the proper dose for most of us? Happily, overdose is not much of an issue, but the optimal approach is to get your level tested, and then to take enough to get your level above 30 ng/ml and, preferably, up to about 50 ng/ml. But the approach that is almost as good for most people is for an adult to take 4000 IU per day during the fall, winter and spring. One could easily take it all year long, too, especially if you’re like most of us who don’t get much sun. For kids, there’s not as much data, but babies can easily take 800 IU/day with no danger of overdose. I would just say 1000/day to make it simple. Kids who weigh more than 25 pounds could take 2000 IU/day. Liquid drops tend to be the easiest form to take and also the most cost-effective—they are usually 1000 or 2000 IU/drop. For further information, check out the Vitamin D Council’s Web site (

Vitamin A is also necessary for proper function of a wide variety of systems; its antiviral activity is the one we will focus on here. This fact has been well known for years. For instance, it may be the reason that measles infection is much more likely to be fatal in Africa, where vitamin A deficiency is common, than here. When African kids with measles are given 50,000 IU of vitamin A, they do much better. I recommend that everyone take a good supplement containing pre-formed vitamin A, and take a higher dose twice daily for the first two days of the flu. The recommended amount per dose: for children under 6 months, 10,000 IU; children 6–12 months, 15,000 IU; children 12–24 months, 20,000 IU; children 2–3 years, 25,000–30,000 IU; children 5–7 years; 50,000 IU; children 7–10 years, 75,000 IU; children 11–14 years,100,000 IU; and people 15 and older, 150,000 IU. Liquid vitamin A palmitate is widely available.

Vitamin C is highly recommended. We think the best form is the packets of mineral ascorbates called Emergen-C. An adult can take several per day, and kids can have as much as you can get in them. During acute illness, the body can use large amounts of vitamin C, so add multi-gram doses of pure vitamin C to the Emergen-C.

We routinely prescribe supplements that contain a variety of vitamins, minerals and herbs specifically designed to help boost the immune system, when we are treating colds, flus or other infections. Zinc and selenium are specifically helpful….There are other similar products available in health food stores.

Happily, an herbal medicine seems to be effective without the troubling side effects of Tamiflu. This is black elderberry, which is readily available over the counter. We would use two capsules 4 times daily at the first sign of the flu. In addition, if a family member should come down with the flu the rest of the family could take it.

I should also mention the homeopathic, Oscillococcinum. It appears to sometimes work to minimize the severity of the flu. You can take a half-tube as a dose, and follow the directions regarding repetition.

What if I am already sick when I go into labor or I contract the flu while nursing my newborn?

Talk with your doctor or midwife about the option of taking an antiviral medication and boosting your immune system via natural supplements. This is usually decided on a case-by-case basis. If you do not opt for an antiviral, keep nursing your baby. It is important to provide some immunity via the antibodies in your milk. To minimize the chance of transferring the virus to your newborn, wash your hands thoroughly with soap and water before nursing or handling the baby. Avoid using alcohol-based hand sanitizers before nursing as they can be transferred to your breast and are toxic to the baby if taken internally. They can be used if you are just holding the baby or changing diapers. Wear a face mask while caring for your baby, especially if you have an active cough. The challenges of recovering from birth, caring for a newborn and managing flu symptoms will require that you have ample help postpartum. You will need to elicit help from friends and family who have been immunized or have already recovered from the H1N1 flu.

I am thinking about getting the immunization. Is the H1N1 shot safe and effective?

GlaxoSmithKline recently unveiled results of a preliminary study of its vaccine, noting that a single dose confers almost 100 percent immunity from H1N1 three weeks after vaccination. The results were from a clinical trial involving 130 healthy volunteers, aged 18 to 60. If you trust reports generated from the vaccine makers themselves, rather than independent sources, this is encouraging information.

According to the FDA, an immunization has to increase the antibody titer to 1:40 in order to provide immunity to the flu. But none of the immunizations can guarantee an antibody rise to protective levels. CSL Biotherapies Inc. reports that only 48.7 percent of people aged 18–65, or roughly half of those receiving the vaccine, will achieve these levels.

In addition, vaccine labels inform us that achieving adequate titer levels doesn’t mean 100% protection from the flu. “Specific levels of HI antibody titers post-vaccination with inactivated influenza virus vaccine have not been correlated with protection from influenza virus. In some human studies, antibody titers of 1:40 or greater have been associated with protection from influenza illness in up to 50% of subjects.”

How this translates is that only 25% of immunized people will actually have immunity.

In terms of the safety of the vaccine, you will find a lot of data online with compelling information on either side. I encourage you to educate yourself before making this important health care decision.

The H1N1 shot is created in the same manner as the seasonal flu shot, which has been administered to pregnant women for many years now. The National Institutes of Health (NIH), a division of the US Department of Health and Human Services, reports that the safety record is good relative to flu vaccines given to pregnant moms, regardless of the trimester in which it is administered. The most commonly reported adverse affect is soreness for a day or so at the site of injection. According to government agencies, serious adverse events are “extremely rare.”

One way to investigate safety is to read the actual vaccine label or package insert that is provided to your physician. One company states [brackets mine] that the vaccine has not “been evaluated for carcinogenic or mutogenic potential, or for impairment of fertility. Neurological disorders temporally associated with influenza vaccination such as encephalopathy [a degenerative disease of the brain], optic neuritis/neuropathy [inflammation or disease of the nerves to the eye], partial facial paralysis, and brachial plexus neuropathy [degeneration of the nerves to the arm, shoulder and chest] have been reported. Microscopic polyangitis (vasculitis) [inflammation of multiple blood and lymph vessels] has been reported temporally associated with influenza vaccination.”

Concerning administration to pregnant women, the insert reads: “Pregnancy: Animal reproduction studies have not been conducted with Influenza A (H1N1) 2009 monovalent vaccine. It is also not known whether these vaccines can cause fetal harm when administered to pregnant women or can affect reproduction capacity. Influenza A (H1N1) 2009 monovalent vaccine should be given to a pregnant woman only if clearly needed.” Based upon that statement, one would typically view administration of the H1N1 vaccine to pregnant women as an “off-label” use…except for the tiny loophole-comment tagged on the end.

Dr. Toni Fuaci from the National Institute of Allergy and Infectious Diseases (NIAID) supports the administration of the vaccine to pregnant women and believes its use is clearly needed. However, he is vague about long-term safety, stating in a video interview that, “It is safe—at least in the immediate safety [sic]“ and ”safe in the short term.” This hedged response is most likely because we simply don’t know. The H1N1 flu shot is new, despite its similarity of preparation to other flu vaccines. Because of the impending flu season, safety testing was brief and involved fewer subjects. Public health experts said that there’s no way to know if any rare side effects will occur in the new vaccine until millions of people are vaccinated. Those unknowns certainly can make an expectant mom concerned about being able to make an informed choice. Reports are beginning to come in from around the world of vaccine side effects ranging from rashes and rare muscle-weakness disorders to anaphylactic shock and death. The percentage of vaccinated people who experience severe complications has yet to be calculated.

Just recently, web postings have been starting to accumulate from women who have suffered miscarriage 1–4 days after receiving the H1N1 vaccine in the first and early second trimesters of pregnancy. There is not enough clinical data available to know if this is coincidental or causal, but the numbers of postings are growing and may eventually generate further investigation.

In conclusion, opinion seems to be deeply divided about the value and safety of the H1N1 shot. Naturopathic physicians don’t generally recommend it for a number of reasons. Many highly qualified individuals believe that there are long-term risks from repeated flu shots. They cite the fact that there hasn’t been enough time to adequately test the H1N1 vaccine for serious, long-term side effects and claim that effectiveness of the flu vaccine program has been “spotty.” They remind us that the vaccine industry and the public health establishment both have serious biases in favor of massive vaccination campaigns, and the media goes along with their pronouncements. While holistic health care providers remain skeptical, the allopathic health care community is made up of the professionals who are caring for those individuals admitted to the hospital with serious respiratory compromise from this flu. Their perspective is one of deep concern about what can happen in those few individuals who become seriously ill. They are understandably passionate about reducing those numbers. It is clear that government health organizations consider the risks of this flu for pregnant women greater than the potential of currently unknown risks from the vaccine. They have compelling reasons to promote vaccination for every pregnant woman in spite of our limited knowledge about long-term effects.

The 1976 swine flu vaccine wasn’t safe. Is this shot made the same way?

The 1976 swine flu vaccine was definitely linked to safety issues. Neal Halsey, MD, director of the Institute for Vaccine Safety at the Johns Hopkins Bloomberg School of Public Health, was at the CDC in those days. When interviewed by WebMD Halsey said, “We did identify an increased risk of GBS [Guillain-Barre Syndrome—a rare, progressive disease causing pain and paralysis] in the six weeks following immunization. What is not known at this time is exactly why that vaccine was associated with that increased risk.”

No flu vaccine since then has been linked to this risk. Halsey guesses that there is the potential for the H1N1 flu vaccine to carry a risk of causing one case of Guillain-Barre per million people vaccinated.

Many journalists have pointed to adjuvants as the ingredient which caused complications in the earlier vaccination program, and there are some good studies supporting this view. Government agencies assure us that the manufacturing process of the current injection more closely resembles the process of the common seasonal flu shot than it does the previous swine flu shot. Thus, the government believes the risk of repeating similar adverse effects is minimal.

What are adjuvants? Should I be worried about them?

Adjuvants are substances added to some vaccines that stimulate a stronger than normal immune response in the body and generate production of a greater number of antibodies to fight disease. Squalene, an adjuvant contained in the mandated anthrax vaccinations given to soldiers, was investigated as a cause of Gulf War Syndrome. The World Health Organization reports that extensive studies have found no connection between squalene and Gulf War Syndrome. However, some very good studies exist which demonstrate a direct correlation between squalene antibodies and soldiers who received the vaccine, including those soldiers who weren’t sent overseas. Every soldier who became sick had the antibodies. Soldiers without the antibodies did not receive the vaccine nor did they become ill. Dr. Jules Freund, the creator of squalene, warned that animals injected with the substance developed the animal equivalents of multiple sclerosis, rheumatoid arthritis and systemic lupus.

US government online sources assure us that squalene is a naturally occurring substance extracted from fish oil and that we all have small amounts of squalene, which we have obtained through food sources, naturally circulating in our bodies. While true, there is a huge difference between how our bodies utilize and respond to squalene when it is consumed in food than when it is directly injected. There is a reason that a federal court judge banned the Pentagon’s use of squalene in 2004. Squalene is not approved for human use by the FDA. However, an effort was made by pharmaceutical companies to fast-track licensure of squalene adjuvants into US H1N1 vaccines under an Emergency Use Authorization (EUA). This fast-tracking can be invoked during a declared public health emergency.

On October 1, squalene-based ingredients were listed on US labels as an additive in the H1N1 vaccines produced by Novartis (as MF59) and GlaxoSmithKline (as ASO3). There has been huge public resistance to H1N1 immunization, primarily due to concerns about squalene in the vaccine. This resistance was apparently successful. In November, US government Web sites stated that no vaccine being manufactured for the US contained squalene. A re-examination of the exact same vaccine labels revealed that the reference to squalene in the contents listing had disappeared. According to Barbara Loe Fisher, founder of the National Vaccine Information Center (NVIC), none of the H1N1 vaccines being distributed in the United States contain squalene or other oil-in-water adjuvants. The vaccines containing squalene have most likely been redirected to Europe, Canada or developing nations with no such restrictions.

If you are outside the US and wish to be immunized, but want to avoid squalene, ask your health care provider to let you see the label that comes in the vaccine package. If you see MF59 or ASO3 listed as an ingredient, that vaccine contains a form of squalene. One company that appears to never have included squalene or any other adjuvant in their H1N1 vaccine is Sanofi-Pasteur.

Are there any other ingredients in the vaccine that should be avoided?

If you choose to be immunized it is important to request that the vaccine you receive come from a single-use vial or a prefilled syringe. Most people will receive a vaccine that is drawn from a vial containing 10 doses. The multi-dose vial contains thimerosol as a preservative. Thimerosol is a form of mercury. We know that mercury can potentially concentrate in the brain of the unborn baby and is known to have a negative impact. As a precaution, it is always important to avoid it in pregnancy whenever possible. One news source reassured consumers, stating that the vaccine contains less mercury than eating a single tuna sandwich, in an attempt to put the dose in perspective. This is a faulty comparison. There is a huge difference between consuming mercury in food, after which it is filtered through the digestive system, and directly injecting it into your body. The single-use vials and prefilled syringes will not contain thimerosal.

The thimerosal-free vaccine may have other unavoidable trace contaminants as a result of processing, including formaldehyde, ethelene glycol (essentially antifreeze—it is used during production to split the virus), phenol (carbolic acid), antibiotics (neomycin, streptomycin, etc.) and beta-propiolactone (which is above the 75 percentile on a chemical hazard rating). Remember, these are very minute, trace contaminants. The potential risks of the flu must be measured against these trace contaminants.

If you are allergic to eggs, you are not a candidate to receive the H1N1 vaccine, since it is currently prepared with egg products. If you wish to be immunized, you must wait for future vaccines that are being grown in animal organ tissue rather than in eggs.

I hate shots. Can I take the vaccine that is inhaled?

Not all H1N1 vaccines are created equal. Unfortunately, the “sniff shot”—which is inhaled via a nasal spray—isn’t an option for pregnant women because the virus is attenuated. More bluntly, it is a living virus that has been intentionally crippled in order to minimize the risk of illness while triggering the body’s immune response. It is very effective, but also carries greater risks of illness or side effects. Therefore, it is not recommended for pregnant women. If you elect to be vaccinated, you must receive an injection.

The government is encouraging everyone to get a regular seasonal flu shot now and the H1N1 flu shot when it is available. Should I get both immunizations?

Unpublished Canadian data is raising concerns about whether it’s a good idea to get a seasonal flu shot this season. Drawn from a series of studies from British Columbia, Quebec and Ontario, the data appears to suggest that people who got a seasonal flu shot last year are about twice as likely to catch swine flu as people who didn’t. A scientific paper has been submitted to a journal and the lead authors—Dr. Danuta Skowronski of the British Columbia Centre for Disease Control and Dr. Gaston De Serres of Laval University—won’t speak to the media. (Journals bar authors from discussing their results publicly before they have gone through the peer review process.) Concern about the unconfirmed findings is playing into calls from Quebec and possibly other jurisdictions to delay or even cancel this year’s seasonal flu shot campaigns across the country. The US has made no change to their recommendation.

This unpublished data creates an uncertainty about what recommendation is best for those pregnant women who choose to be immunized. If the primary concern is protection from the H1N1 virus, omitting a seasonal flu shot and waiting for the H1N1 vaccine is probably the best choice until we learn the details of the Canadian studies. If you elect to have both immunizations, consider having them administered at least three weeks apart to minimize chance of overtaxing your immune system and provoking side effects.

If I am immunized, will my unborn baby have protection from the flu after it is born?

Assuming this vaccine follows the record of seasonal flu injections, it will provide immunities to your unborn baby as well. So will illness with the actual H1N1 flu while pregnant. It takes three weeks after being immunized or contracting the illness for your levels of antibodies to reach their peak. Antibodies passing through the placenta or through breast milk after the baby is born will help protect him or her in the first vulnerable months of life. It is recommended that babies under the age of six months not receive flu shots.

My baby is already born. If I am immunized now, will it hurt my baby?

One vaccine company’s product insert addresses this issue, stating: “Nursing: It is not known whether [the vaccine] is excreted in human milk. Because many drugs are excreted in human milk, caution should be exercised when this vaccine is administered to a nursing woman.” It is thought by the medical community that the risks to the newborn, if it contracts flu, are greater than the risks of transmission into breast milk of the vaccine components.


Government sites:

To research vaccine contents:

WebMD article on safety:

Practical steps to protect yourself from contracting the H1N1 flu:

Journals, news advisories and Web sites on flu in pregnancy, vaccines and antiviral medications:

Information on Squalene:

About Author: Maryl Smith

Maryl Smith, CPM, LDM, has an active homebirth practice and has been catching babies since 1984. Over the years she has cared for women from over 18 different nations, worked in two free-standing birth centers, taught as adjunct staff at Birthingway College of Midwifery and served in multiple roles in the promotion of midwifery in the state of Oregon. Her passion is supporting trauma survivors during the perinatal experience. Maryl frequently travels the world with her pastor/musician husband working to preserve indigenous spiritual expression in music. Her other activities include adventures with her granddaughters, herb gardening, writing and being active in her local Native American community.

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